Thanks for your inputs. I talked to Schneider today. I guess I misread their add on new style mechanical valve lifters. Schneider sells them for the Chevy 235/261 with 0.848 diameter. The GMC lifters are 0.990 diameter. The old milk can shaped lifter is all that is available.

I have looked on line for GMC mechanical lifters with 0.990 diameter with no success. They look like hydraulic lifters.


FranK Hainey