[Mgs] Removing Carbon Build Up on Piston Heads

[Robert J. Guinness]

My American Muscle Car buddy suggested using spray on oven cleaner to 
remove carbon build up on  the tops of my pistons when they are still in 
the block.  After removing the head, they bring the cylinder to TDC, 
spray, rotate down, then sop up the dissolved carbon with paper towels 
or rags in about 30 minutes.  Has anyone tried this on an MG?  Will it 
hurt any "delicate parts"?
-- 
Robert Guinness