You better check if it is allowable to remove 16 thousands. You might find there is a thicker head gasket available hopefully if needed.

Three thousands is the limit for the old cast iron heads I believe. Hope the guy that surfaced your head used the book that auto machine shops have. This tells them the allowance for material removal on all makes of automotive heads.

Maybe you are allowed 16 thousands I just do not know. You have to really check this out. This is a 169k engine? Should not need three exhaust valves since it has hydralic lifters. Maybe someone dropped a higher milage engine in this car at one time. Although there can be exceptions to the rule I suppose.