Yeah I agree Bullitt, you would think that would be the case. Seems now the cheaper aftermarket pistons are more "generic" and compression heights don't follow the factory as closely anymore. It's that way with many brands of engines now, I ran into the same issue with a 351w I just built for a customer. It's just the nature of it today.
To get it right and have tight quench takes a bit of work now. Just can't buy a piston off the shelf to fix it (unless you get into custom stuff $$$$). What I always end up doing since these 40+ year old engines need to be decked anyway because they are so out of square, is taylor the compression height and how much needs to be decked and attempt to keep the piston about .007 in the hole, which saves the deck for future rebuilds. I never like to take them all the way down.
The Windsor I mentioned had .013" taper on the deck from one end to the other so we shaved a lot to square it up, and selected a KB piston, set everything up .007 down in the hole. In some cases you get into custom pin heights to get the compression height where you want and it starts to get pretty expensive. Just went through this on my DZ using JE pistons so we didn't have to widdle the block so much. There's really no cheap way to achieve tight quench anymore.
Given the example above, even the KB piston with the compression height he is looking for is still going to be .022" in the hole if his deck height is a stock 9.025. That's not good enough in my opinion if I were building this from scratch. Shaving .022" off the deck is a bit excessive too. Plus I'm willing to bet the deck height is probably a little wanky if it's untouched. Probably a little higher or lower on one end or the other, they almost always are if original. So at a minimum it would have to be squared up. Once that's done things would be a little tighter, how much it's hard to say until you dig in, but it takes some work to get these things right, and he would likely end up looking at different compression heights to dial it in.
