The oil pump drive gear and shaft need to be installed correctly so you can get the distributor installed correctly so you can set the ignition timing correctly scope
I would buy a factory service manual for the year of that block so you can get all the factory correct torque spec, clearances, wiring, adjusting the throttle linkage and kick down settings for the tranny and so on and installing the oil pump drive gear and shaft correctly scope
As far as low oil pressure on Mopar oil pumps, BB and SB, remove the plug (drill a small hole in the center and use a sheet metal screw to pry it out with claw hammer or nail removal bar, weld the hole up and reuse that plug if you can't find or buy a new one) covering the oil pump bypass valve and see if it (the valve) is stuck partially open due to grit or debris scope
That or buy a new pump and try that work
Good luck either way up
Welcome to Mopar land and to all of us that harass the uninformed and newbies telling us to change us over to GM or Ford cars and parts down
Chevy for breakfast, Fords for dinner boogie

Last edited by Cab_Burge; 08/16/21 05:44 PM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)