Would lifter trays that are rotated 180 cause any issues. Already have the head bolted down and don’t want to take it apart if I don’t have to.

 

Pretty sure they are jammed up against the block and can't "float" on the lifters like they're supposed to.

I don't think they'll survive very long, and when (not "if") they fail, it's gonna cost you A SHIPLOAD M\ORE to fix what happens (turning sideways and EATING lobes and rollers), than a pair of HGs.

 

It'll be fine. The early blocks don't have locators anyway like Gen4 blocks. They are still the same dimension just with locators.

 

This They are "central" IIRC, meaning they're reversible. However, years ago, some guys drilled 1/2" (?) diameter holes in one side of the trays, to aid oil drainback. If thats the case, they should go in however they came out. I cant remember if the holes faced inward, or outward.

 

They face outward. so as to allow the oil to drain downward. 1/2" is a little much. I drill about a 3/8" hole. I started doing this about 2004 and built many many engines using this method and never had an issue. It's so much cheaper than link bar lifters.

 

The ones I have with 1/2" holes were modded by Kurt Urban or Billy Briggs when both were still at Wheel to Wheel. I never had a problem. I won't disagree with you, however, as you would think 3/8" would be large enough. Maybe in a roadrace app the 1/2" may have some advantage, so maybe that's why, IDK.......