You may get away with that with a completely stock, untouched engine but it's still not right. And hopefully you won't collapse a lifter or bend a push rod. You can only check/set lifter preload with the lifter on the lobe base. http://www.cranecams.com/uploads/instructions/151g.pdf
I did it many times and it was never wrong. Totally unnessary for bolt down pedestal rockers to do it any other way. If you bend something, something else caused that.
Didn't need to check it for a lo-po motor. Done it with both the stamped steel rockers and Cobra rollers. No problems, issues or anyother negative consequences resulted from it. But hey, if that's the way you want to do it, knock yourself out. But it's not a nessecity to do so. More attention should be paid to roller pushrods, that's what really wears in a roller motor with pedestal rockers.
I never saw that it stated what type of rockers he has. This can cause all kinds of confusion. Old style adjustable like chevy roacers...early 70s came with the rail style no adjustment just torque them down..then the pedestal style
I stole the thread, so I'm guessing u're talking about me.. I'm thinking they are rail or pedestal from pictures and descriptions. Detailed pictures were kinda hard to find. They are not rollers and are bolted in by a single bolt on top that goes through a little block, through a U-shaped bracket/trench/rail type things and threads into the head. There is one bracket/trench/rail type thing for each pair of rockers. Does this make sense? Camera phone is broke, or I'd take a pic for ya.