.062 holes in the bushings are huge....... as are the .040 in the pushrods.

.020 is plenty big.

Did you check to see how much leakage is coming out around the lifters at full lift while priming?

68 Satellite, 383 with stock 906’s, 3550lbs, 11.18@123
Dealer for Comp Cams/Indy Heads