I successfully changed my first timing belt/water pump/drive belts/cam and crank shaft seals thanks in large part to the info here. I'll share some tips from it here that I put on the npora facebook group a few weeks ago:
My first timing belt replacement is done. Pathy runs smoothly. Replaced timing belt, water pump, cam and crankshaft seals, coolant hoses, and drive belts. Here are a few tips for anyone who tries this in the future...
The 1A auto YouTube tutorial on R50s is superb. Following it will set you right - https://youtu.be/awjqoFUUPSo?si=6Avjp9Q6ivaIk-UO
the Nissan repair manual is good to have as well. (get it on the NICO Club forum)
Use the OEM crankshaft seal. I went through 3 seals because the inner lip would get caught on the shaft and fold under. The Nissan seal was built better (and pre-lubed)
The harmonic balance puller is fantastic for pulling the crank pulley right off. I bought a kit for like 20 bucks on Amazon (you can also get a loaner from the autoparts store), and got the bolts for it at the hardware store (m6 x 1.0 x 75mm - same size as the long upper left bolt in the lower timing cover)
An impact wrench is key. Used it for getting off/on the crankshaft bolt and the cam bolts without turning the shafts. I also used a camshaft holder tool once the belt was off.
I debated on whether to remove the air compressor like the video suggests or try to jimmy the timing cover off around it. I was able to get the timing cover off with some work, but getting it on was tougher, and scary (I didn't want to break my A/C or mess with my timing bel. Moving the compressor was easier than I thought.
The power steering tensioner bolt was a PITA because of where it was located. a 12mm ratcheting wrench would've been nice
Tighten your belts. The first time I turned on the engine it was like the loudest chalkboard screech I've ever heard.
Finally, there's a right-angle coolant hose that sits behind the timing belt cover that's a PITA to get off/on. I ended up having success using a chisel to pry it on. Make sure the clamp tabs aren't facing out when you put the timing cover back on, or it can bend the cover, possibly interfering with the belt. I of course read this in the repair manual after the cover and cam sprockets were back on.