On an iron headed engine, cometics are wasted money unless you're trying to rig it for compression of one sort or another. I'd like to see how well wet or dry holds up to a block's deck. Iron is not urethane, and paper looses abrasive like mad. That's why machinists use emery cloth. Cometics have their place. 90% of engines regardless of head material dont need them. If you have to use them for the performance level you're at, machie it right from the start for them. Before you tear too much into the cooling system for leaky studs, try letting the engine heat cycle a few times. I've had a few that stopped on thier own after things found their equilibrium.