I just purchased a set of carbide-blade hand turned cutters from an Ebay seller that can be used for the recessing operation. Each one of the different size and angle cutter heads also has a set of blades on the back side that are usually used to narrow the valve seating area from the top. For instance:

www.ebay.com/itm/394349427127?

Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!