I've had this idea in my mind for a while. Sorry if I sounded noob

I've been reading k20.org for a bit and I've came by quite a few thread where it's basically:
"I've got mailed TSX pistons instead of my CRV pistons... I'll just swap them out and reflash...bam! compression ratio increased from 9.7:1 to 10.5:1.... goody"

hmm... is it THAT simple?

If so then can I swap out a set of K24z3 piston's (11:1) onto my CL9 (K24a3, 10.5:1) to get more out of the block?