Getting my compression right

If you have the PN of the KB pistons, that can all be figured out, IF the block deck is stock. Find the piston PN and let us know. There are 6 different KB's for the 360.....

If you don't know whether the block has been decked or not, then to be sure, measure from the deck down to the top flat edge of the piston at the upper edge of the piston. Also look to see if there is a small step up in the top of the piston in that area, then that is a KB232 or KB373. ('Quench head') Post pix of the pistons if you can.

Once the height if the pistons relative to the deck is known, then the CR can be computed pretty darned closely.

So when you say 'cool 'er off', do you mean it is running thermally hot? or detonating or what? OK, I see.... you want to run on pump gas. You can do that with more than 9:1 Static CR.