<VV> removing carbon from piston tops (with heads off)

[Ray Rodriguez]

     Sunday I'll be dropping off my 140 heads to get warmed over by the Corvair Ranch at the open house.  This engine was running very rich previous to disassembly and has considerable carbon deposits in the combustion chambers.  I'd hate to install my freshly reworked heads onto the jugs with cruddy carbon topped pistons....  

     Is there any good method or chemical for removing the carbon from the pistons while they are in the jugs?  I really don't want to take things any farther apart at this point unless I really need to.  

     Also, is there any way for me to tell what type of pistons I have by looking at them without taking them apart?  This engine had a cam and deep dimpled lifters installed by previous owner, and the cylinders look fresh inside.... I'm hoping the pistons were upgraded too, but I don't know how to tell.  Whatever they are is what they will remain, but I'd like to know what I have.

Thanks!

Ray Rodriguez