low oil pressure rebuilt 318

I used to have an 88 D100 with a roller 318 in it
That was my first exp with "302" heads.
I pulled the heads and sent them out for a valve job. They wound up being cracked.
No problem I thought. I have a set of 318 heads at home, I'll just put those on. WRONG!
As soon as I started it I found out I suddenly lost oil pressure /that was great, before the head swap. That's when I found out about the 302 heads having bigger pushrod holes, my lifters wouldn't shut up. Because of the roller lifters being longer and the pushrods shorter that changes the angle the pushrods sit at. They were binding in the pushrod holes. I had to get another set of 302 heads to make that motor happy.