I am rebuilding my 01 LS6 after a failed #7 piston. How dirty do my heads and valves look? Should I have a brass wire wheel and clean every valve until it is carbon free? Combustion chamber? Exhaust ports? Thanks in advance.

 

They don't look bad. But I would say go ahead and clean everything up. Why not, it's all apart.

 

A wire wheel bench grinder works great to get all the carbon off the valves. Take a cartridge sanding roll to the bowls to blend the seats and casting flash before lapping the valves in. Also a coarse red scotch brite pad makes the valve stems look new again, especially when cleaning them in a parts solvent tank