Kenny (PDUDE) at Kens Speed and Machine specializes in Pontiacs and can get pretty good pricing on dished pistons, not cheap by any stretch though. http://www.angelfire.com/fl4/pontiacdude428/
Most factory pistons are thick enough to mill a little out to create a dish though or even mill some off the entire top since they are flat tops with reliefs.
But I'd cc the chambers and check piston to deck ht first, chances are it's lower than 10.75 already. You might could find some .060 head gaskets as well. Other option is change the heads to one with a bigger chamber. Check the right side bar on Kens web site, there's a list of head numbers with cc's there.
Wanting a Custom fit in an off the rack world.
I don't have time for a job, I just need the money.
