Correct way to measure piston depth?

Is this the correct way to determine how deep in the bore a piston is? This is a stock '74 318 and I was trying to get an idea just how deep they are. We are planning to use KB167 pistons in the rebuild with 302 casting heads and I am trying to get an idea of how to get to a 10 to 1 or close compression ratio. Mill the heads? Deck the block? We have good 93 octane here. As always thanks for the help!

Author: admin