With the blessing of Eddie Young, I reused my stock ZZ502 dog bone lifters on my Gen6 and the fit was great. The lifters bottomed flush to the top of the dog bone and there was a good 1/8” left before it would start to lift it. There are some folks that speculate that they can’t hold higher spring pressure but I can’t say yet either way.

Just to be clear I’m using the Comp Cams 525EFI clone that has identical lift and duration, and Comp recommended their own dog bone lifters that are identical to GM with that cam. The 741 may have a different base circle.

The comp cam should work with cheap lifters. This is what i found:

Crane 168741
236/244
298/306
0.610/0.632
112 lobe

525 EFI
236/244
298/306
0.610/0.632
114 lobe

comp cam 01-446-11
235/243
289/297
0.610/0.627
114 lobe

Lifters for comp cam are 900-16 and costs $214, but i don‘t know if they work for the other both. Other question is if the comp cam makes less hp. The 114 lobe could be good against water reversion.

Fwiw, the Comp Cams short travel lifters are the exact same height as the stock GM units, so even after you set up the geometry you can switch them out if need be without reinventing the valvetrain. You will need new pushrods with a new cam. I think mine needed about 1/4” shorter.

The reason I went with the stock lifters was they had low hours and we’re proven to work. It seems like everything I read said to buy two sets of lifters just to get enough that would work.

You bought 2 sets of lifters for one build? You must have 4 valve heads LOL.