I know of several roller lifters on the market that have the body designed to work WITHOUT having to bush the lifter bores on an OE tappet block. I run a set of cranes that do NOT uncover the oil hole, and have had no issues whatsoever. They DO however require some block grinding depending on how bad your core shift is...I think there is another smaller company that makes drop in rollers now, that still don't require the lifter bore bushing, can't recall the name though.
not trying to hijack, just wanted to point out the option is out there.
