Yes, I put paper towel in the ports for the lapping and plugged the ports in the engine. Lots of brake cleaner too and some pipe cleaners. Used hylomar but not happy so cleaned it all off and did it again. Knowing myself I'd bought 2 gaskets, should have bought 3 as I managed to damage one. I'm a bit obsessive about grit, when I got my cases / crank back from the machine shop they were far from grit free and I spent hours pocking out every nook and cranny. The machining was good but I would have expected parts to come back clean, perhaps I'm expecting too much?