Yes, those figures agree with the measurements I've made. The next step is to mock up a single cylinder valve train on a head and block I've got on the stand to see if the angle of the pushrods created by moving the rocker pivots inboard to get the proper sweep of the rocker tip across the top of the valve stem can be accomplished without interference with anything. The different angle of the intake and exhaust valve stems on the stovebolt head is going to be an important consideration. The modification would be a lot simpler on a GMC head.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!