Then be careful which lifter you buy. If your block isn't tubed, and the lifter body has a big cutout in it, that cutout can open to the top of the lifter bore and you lose oil pressure.
I hope that the builder at least opened up the feed holes from the oil gallery to the mains. I've seen those things that were way small...like Chrysler didn't finish drilling the hole all the way.
You have to check and verify everything at your level or you can get bit in the ***.