combustion chamber size

My compression is going to be a little high if I put the heads on as they are now (60cc's measured). Need to be around 65cc's, I plan on basically removing a little material off the entire combustion chamber to get the additional 5cc's out of it, is there anything I should watch out for. These are GT-40P heads.

not a good idea me thinks. 5cc is alot.
what compression you think you will run with 60cc?
[addsig]

Exactly what piston are you running? Is the piston down the bore or above the deck?
[addsig]

With a 60cc chamber my comp. will be up around 10.6, and I don't want to put a big cam in it so my intake valve closing time will be earlier/average not later and my dynamic comp. gets too high.

The pistons are Keith Black 192's, have a 12cc dish.

Planning on keeping the quench down around 0.045, right now the pistons are below the deck by about 0.016 (from block measurements), but until I assemble the crank/rods/pistons and measure all bets are off. Will take some off the block to keep the quench where I want it if I have to, the head gasket thickness will be .039 or .041 so the pistons can be down a little.

What head are you using?
[addsig]