Decided to go roller

340sFastback said

Hydraulic rollers tend to be taller then flat tappet and that changes the push rod geometry requiring push rod holes in the head to be clearanced.

I would put the cam/lifters in the engine, run the oil pump with a drill, and rotate engine by hand to make sure lifter oil grooves are not exposed at max lift.

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Yep you are correct about the heads needing some clearancing. I need to chamfer the push rod holes just a bit near the intake side. I did one hole yesterday while the heads were in just so I could measure for push rods and to check geometry. I had to shim the rocker shafts which I guess is common on LA iron heads. The geometry changes quite a bit with the 1.6 rockers and these roller lifters. Fun experience so far.

BTW. I made sure to cover everything up and use a vacuum to avoid metal shaving from getting into the engine. No work to be done on the block as advertised.