Help with decking or not?

If the deck is at the nominal 9.600" deck height, then your SCR will be right around 10.5:1 with those .039" head gaskets, and the Icon pistons given before. I agree with the above that .051" gap has some use, though not optimum, but the AL heads help with detonation avoidance anyway. But can't agree that AL heads 'like' a particular CR.....

One you get things together, measure the rod length and CH on one piston/rod set, and use that to move around to each cylinder and check the deck height, to be sure you have what you think. (You'll have to assume the stroke is the same on each crank throw unless you measure that too.) Deck might be high or might be low.... I have a factory 273 block that is low all around and is .008-.009" low on one corner. So you never know 'til you measure.

What is the planned use for this engine? Any idea on the cam?