not much just want to fill in the floo so ts flat, and dont do moe than round out corner at valve seat dont an to cut it down just smooth it round ,
I pot exh to gasket yes afte market make a gasket and keep floor flat make a BIG D its hard to reach alot of the port but a die grinder a band sander and few other tools make it work . roll sanders ect. dont have a picture yet but unshroud the valves but dont go too far you dont want to go past gasket and flaten out spark plug boss on intake side so air flows over it ill take pictures of bowl work soon as my camera batterys charge