Slartibartfast

So it's going back and forth between good and high? The mixture's actually supposed to bounce back and forth a little when it's in closed loop, that's how it controls the mixture with a narrowband oxygen sensor. Maybe the sensor's on its way out and it's responding very slowly? There is a test mode for the oxygen sensor, might be worth running that to see if the light's flashing like it should. Some codes don't trip the light, so I'd run those too on the off chance.

The torque spec for the bearing lock nut is 4.3-13 inch pounds--just enough preload to get the play out of it, plus what it takes to get the screws in. Sounds like you ran yours at roughly 70x their intended torque. I've never run a bearing that tight, but yeah, I'd lay money that's your problem. I don't think I'd trust that set of wheel bearings to go again.

That's a weird one. Wonder if someone popped a fuse somewhere else and "borrowed" it? Glad to hear it was a cheap/easy fix!

My (limited) understanding of the SFD is that it's basically the unibody equivalent of a body lift. Suspension lifts mess with the front end geometry, and cause more problems the higher you go. IIRC the R50 gets unhappy if you go past about 2" of suspension lift. A body lift or SFD leaves the geometry alone and just shims the body up over the existing suspension. So apart from the higher center of gravity (which you'll get from any lift), I wouldn't expect the SFD to make much difference to the handling and alignment--or at least it'll work better than it would if you tried to lift it the same amount by modifying the suspension.

I had a look at the circuit diagram on EL-251, here. If we assume that the two faults have a common cause (not guaranteed, but does seem likely), then it's gotta be between the battery and the cruise switch on the steering wheel, because that's the only section where the cruise and horn circuits overlap. The clockspring has a wire in it that's shared between everything that's not working (horn and all cruise buttons except "main," which I assume is the one that works). Naturally you've already replaced that. The coil in the relay could also break both circuits if it was bad, but you've replaced that too. That leaves the switches/wiring inside the steering wheel, or the wiring between the battery and the wheel. I would start by testing fuse #52, 7.5A, which runs one of the horns (for some reason the two horns are fused separately), the horn relay (which means this one fuse will still take out both horns if it's bad), and also those three cruise buttons. Check with a test light (with the other end grounded) that you have power at both legs of the fuse. One leg means it's dead, neither means there's an issue between the fuse and the battery, both means it's OK. If there's power at the fuse, then it's a question of what you want to tear apart first. I'd be tempted to tear the wheel apart first and test that it's getting power at pin 1 (pin 12 of the clockspring), as labelled on EL-253. (I'd test this with a meter, because the resistance of the relay coil might be too much to work an incandescent test light.) If it's got power, I'd test the switch next. If it doesn't, then there's a break between the fuse and the switch. In that case I'd check the other side of the clockspring (to verify the clockspring's good), the connector on the light green/black wire shown on EL-253 (no idea if that connector is just that one wire, or a bunch of them, but it would be a convenient test point if you can find it--or a possible source of the problem if it's loose/damaged), and the horn relay connector. Once you know which two points you lose power between, you know what part of the harness to investigate. Hopefully it's not the harness. That's all I've got. Good luck with it and let us know when you figure it out!

Yeah, it's not a big engine. I took apart a VG33 a while ago and was able to carry the block around pretty easily, and I'm not exactly corn-fed. I saw a guy on Youtube put an LS in a D21, and he ended up notching the crap out of the firewall to get it in there. Ecoburst could be entertaining, and Nissan got a four-pot in there, so surely there's room. Speaking of, there's also a kit to bolt a VW diesel to a Nissan gearbox.

The diff sure ain't light! But neither is the gearbox.

I haven't measured mine, but this guy says 22". Which engines are you looking at?

Good lord. And here I thought I was pushing it at half that!

Looks like the VG and VQ R50s used the same trans mounts, and they are still available aftermarket. I looked it up for '01 and '97 on RA (I know you can't order, but it's still a good parts lookup) and found Anchor 9011 and Westar EM9011 marked as rear/4WD/manual. I punched the Anchor PN into the Gargler and it spat up a few other vendors listing it. Hopefully one of them actually has it in stock. The second PN comes up as some kind of damper rather than a mount. Possibly an NVH thing? If so, I'd be surprised to find one aftermarket.

I had a weird clatter turn out to be the front bearing in the alt giving out. Remove the accessory drive belts, run it, see if the noise goes away. If you do them one at a time you'll know which one is noisy. I would also give the water pump a spin, see if there's anything obviously wrong there. Given the front-end wreck, I'd also check that the fan shroud is held on properly, and the fan isn't making contact with it. Long shot, but worth checking. If it still makes the noise with all the belts off, might be worth pulling the timing covers to check the belt tension and the condition of the idler pulley. IIRC the keyway only locates the sprocket during assembly, and it's clamped in place by the crank bolt. So unless the crank bolt is loose, it shouldn't be able to rattle.

Those look like a smaller lug pattern. Looks like the D40 Fronty went to 6 on 4.5" rather than 6 on 5.5". I would assume the D22 Fronty wheels would fit the lugs, but I don't know what they had as far as diameters and offsets and whatnot.

I've heard of the dampers causing bleeding issues. I don't think I've heard of one doing what yours is doing, but it does sound plausible. If nothing else jumps out at you, look for an M10x1 invert flare (not bubble) union. And yeah, I'd check under the dash first, if only because I hate bleeding hydraulic systems.

I haven't seen him around in a while, but Ekim Naelcm on the NPORA FB page did a TD swap. He would be the guy to track down with questions, or see if Farcebook lets you dig up his old posts about the swap. The gear ratio should be marked on the tag in the engine bay. US trucks are HG43 or HG46, for 4.3 or 4.6 ratio diffs. Hopefully the Terrano is marked similarly. If the '95 is auto, it's more than likely HG46. Manual trucks usually got HG43. If you plan to run stock-size tires, and the ratios are wrong, that'll throw off your speedo. But if you plan to run larger tires, then the deeper gears would be an upgrade. I have a service manual for the TD27, but sadly not the full manual for the rest of the truck, so I don't have a schematic for the glow plug wiring. However, the '87 Pathy/Hardbody manual that I do have shows an SD25 diesel engine, which has an automatic "quick-glow" system wired from what looks like the same ignition switch as the gasser. If you want I can take a few pictures of the relevant pages in the manual. That said, I suspect you'd be better off reverse-engineering it from the donor (or just swapping over the harness and everything attached to it!) than making assumptions based on service info for an earlier engine from a different family. Good luck, and let us know how it goes!

The classic symptom I've heard for slipping rack bushings is that the wheel centering keeps changing, especially after turning to full lock. I wouldn't expect it to only act up in one direction, unless maybe one bushing was much worse than the other. Worth inspecting them if that's the last thing you did before it acted up. I would have someone turn the steering back and forth while I watched the rack. Should be pretty obvious if it's moving around. Check anything the alignment guys touched (or should have) while you're under there.