I once bought an unused 200 block which had been machined for wire rings. got the deck planed and it took 0.75mm to get down to a flat surface which meant it lost about 5cc of combustion chamber which may or may not be a problem depending upon what you do with pistons, head gasket thickness, head thickness etc.

i dont know what wills rings are and vaguely recall that it was supposed to use welding wire to get a better grip on the gasket but if the depth of the machining you have is similar then it might worth looking at