Expres post of course!LOL, i would try to get 30 thou. The smaller you can run without hitting, the better. If the pistons sit 10 thou proud over the deck, and you run a 40thou(1mm)gasket then you end up with 30 thou. You may have to machine the dome of those pistons down a little, as a rough calc gives it 12.1:1 comp, but you should bore and hone the block, then dummy assemble the bottom end. Then do all the measurements, and figure out what needs to be decked how much, then your home and hosed. Just remember whenever you build an engine like this, treat it as a custom job and dont rely on anything written on the part boxes, as a small difference here can make a huge difference in compression.