I agree with Oldskool, don't use deck/piston height to attain C/R. Try to get the most quench you can. A zero deck clearance and a 40 thou compressed gasket will get you good quench, better to buy dished pistons or have yours milled. A 3" dia 80-100 thou dish should net you around 1 to 1.5 drop in compression ratio. A D shape is even better for increased quench area but I'm not sure what it would cost to get that done. Good quench will improve fuel air mix, result in a faster burn and should lower chances of detonation.
Back in the 'good old days' when gas was going from 100 octane rating to the crap we now have, it was common practice to put in thicker head gaskets or even double them up to try and reduce detonation, the reduced quench offset any benefit of lowering the compression ratio and it failed as a cure.
