There's a lot of ways to do it. I have done a few. 69 blocks are shorter deck as you've already realized, and most stroker kits are set up for 9.500" deck before cleanup which usually gives plenty to cut for zero deck. The 69 not so much, so you have to be careful with 'em. Mark will steer you right on them. One of the better runners I put together was the same 69 block barely cut to square up, 6.300" rods and 331 pistons. Had to fill the block as the owner wanted high compression-and he got it with the domes. It's been 5.60's quite a few times with DA's below sea level (rare air), typically 5.80's at 117, 2710lb. Can't believe it stayed together as hard as he was on it. He's sold that and having another built as we speak, well ported CHI intake and Kuntz/Brodix HH heads, he's shooting for 1000hp N/A and might actually do it based on what I've seen of it. 462".
Mark I have a question. If he cuts the pistons, do ya think he would have to re-cut the valve reliefs?
'92GT, 427" and '93 "LXVO" coupe