5.3 lifters in 3800 FAIL!!!!!!

ok so i completly rebuilt my 3800 new crank bearings cam oil pump timing cover everything. Got it all together would only build maybe 8 pounds of oil pressure cold while idleing so pulled the timing cover off and checked everything all looked perfect so statred to think of another reason. So i pulled the oil galley plug out of a spare engine i had and put a spare 5.3 lifter in it and when the cam lifted the lifter all the way it actually unblocked the oil galley hole. ill post a picture of the lifter and u can probly notice.

Retype this so i don't think i'm reading a text.

uhm so you put a different lifter in and it block the oil passage? so lost here.

In for more answers... confused

My head hurts.

5.3 mustang lifter or what?

4B11T lifter set