Also depends on how far you are going into a rebuild. Are you gonna overbore, or just rehone the cylinders, rehoning can be done at home. Are you replacing the pistons and rods, or just the rings (also dependant on if you overbore).
One major thing you ought to have done is get the crank checked for wear at the bearings and might as well have it rechecked for balance.
For the heads; Regrind the valves, get new valve seats and new seals, have the cam checked for wear on the lobes. Replace the valve springs, can probably keep the old retainers though.
Something else you could do while it is fully torn down is smooth out any rough casting spots inside the block, but be carefull not to grind any spot too thin and cause a weak spot at a water jacket or oil passage.
Tons more little things, all depends on what you want in the end and how far gone it is now.