Run a tap down all the holes in the block to clean them. Clean any bolt that you are re-using. I like to use gasket sealer on any bolt that goes into a water jacket. Be sure to follow the torque sequences from the manual. If you don't have a manual start from the middle and work your way out in a circular fashion. Make sure you space your ring gaps on the top two rings opposite each other at 9 and 3 o'clock. Check your ring gaps in the cylinders before putting them on the pistons. Check bearing clearances with either micrometers or plastic gauge. I like to put a spot weld on the oil pick-up where it goes into the oil pump. Had one vibrate out once and cost me a spun bearing. Check the clearance of the oil pick-up to the bottom of the oil pan, you can do this with a lump of modelling clay. Abouyt 1/4 inch clearance should be good. Put a long bolt into the front of the cam to make it easy to handle as you slide it in. Make sure you put plenty of cam lube on the lobes. If you are using hydraulic lifters, set them in a can of oil and use a pushrod to push on them to push air out and they should fill with oil. Get some 3-4 inch pieces of 3/8 diameter plastic or rubber hose and put them over the rod bolts as you install the pistons, it guides the rods on to the crank and keeps from nicking the journals. Use plenty of oil as you assemble it. I guess these are all basic engine building tips not peculiar to a Chevy. Anyone have some more or corrections to mine fire away

Pat