A standard bore 72 and later 440 piston will give you a 1.93" compression height, same as 68 383 but it will be .070" over, I machined and built a lot of them and have another I'll be doing soon which will be for sale.
.0042" per CC is the correct number and .00123" must be removed from the itake surface for every .001" that is removed from the deck surface and if possible .0017" from the end rails.
It's pretty common knowledge that many of the fast Max cars in Stock are using an aftermarket low production mani made by A&A that has never been approved as a replacement, if it was, NHRA has never listed it anywhere.