SB engine rebuilding got ya! School is Open!

always use a brand new oil pump if you have the $50 to spend. it will pay for itself.
use a high volume pump if it's a performance engine. high pressure pumps can lead to troubles if it's a stock-type oiling system and not an all out race build with external oiling, restrictors etc... a high volume pump is generally sufficient. use a good oil pan with extra capacity and matching pickup if you can afford it.

all clearances should be checked. every bearing. learn to love plastigauge. all bearings should be pre lubed, preferably with white lube before initial startup. fill the oil filter with oil. use a distributor shaft to prime the oil system as well.

use good gaskets. cheap ones will end up having you tear things apart to replace them. such a pain in the butt just to save a few bucks.

everything should be clean and oiled as you assemble. ring end gaps should be checked.

everything has a torque specification... follow them to the T. use a good torque wrench.

your rods and pistons should all be weight checked and balanced with your crank.

use new head bolts and rod bolts if possible. especially if you dont know the history of some of the bolts you dont know if someone overtorqued them or ran the engine like crazy etc.