Steve, Just got my Crower .200 offset lifters after a 6 week wait.
Same lifters you tried in your IA 2 block. Fits my IA 1 block with over .100 clearnace between the bar and pad.
Will take pics, take measurements and send them to see if they made any changes in the top location of the bar in reference to the lifter itself.
In reference to roller lifters.
I remember that the first blocks Dick sold had the pad too high and the second batch had them machined lowered. Mine is factory lowered, as were the other 2 IA 1 engines I built. Never was an issue.
Maybe the specs were never changed on the original plans when the changes were made ?
I don't know.
Getting into the larger diameter lifter with a wider roller. Gonna be some work so be prepared,
with the valley wall moved closer to the lifter bores to accomadate the thicker cylinder walls for proper water flow on the top side. Grooves are cut now and some have to be even ground deeper then what the factory cut just to fit a stock diameter lifter. Look at Steve's pics on the lifter back wall. But Can be done.
Not talking trash and don't want it to be conceived that way, just putting info out there. Just FYI.