Yeah, tell me about profiles vibrating! My GP P-38 is a pain. I was thinking with going something along the lines of what Jimcork has done. Just run a couple hard wood rails down the side attached to a 1/4" firewall and then bolt those onto the nacelle farther down closer to the wing. As for the front of the nacelle I would just glue some hard wood blocks on the front of the firewall and mount it like a cowl. I just finished cutting out the firewalls I just have to go buy some rails but I dont want to go jumping the gun until I get the airplane and plans. (If I ever do!)[:@]