RE: Gas Powered World Models P51 GS
The upper engine cowl was now ready to put into place. All 3 pieces of the cowl are pre drilled and pieces of plywood are inside the fuselage. The upper cowl comes with a clear plastic cover. It is good to use to fit over the engine for fit. The screws come with silicone washers. I didn't like the way the washers crushed on the cowl so I drilled the holes a little larger for a better fit. The silicone washers have a step on them. When I drilled the small guide hole for the top screws, the drill did not hit the plywood inside the fuselage. Seems the plywood inside was in the wrong location. All I did was cut 2 small pieces of plywood and used thick CA to glue them in place. Then the top cowl screws were secured.
The lower rear cowl goes in place next. 8 screws with silicone washers. There is a problem with the 2 most rear screws. While holding the wing up to connect the servos, the edge of the wing will hit the screws. The silicone washers make the screw heads stick out just enough for the wing to catch them. This causes the screws to break out. The wood blocks are balsa at this point and are easily repaired. I removed the silicone washer and used a flat washer instead. The lower rear cowl doesn't hold any of the load, so it should be OK.
The lower engine cowl will have to be cut for your engine. Since I used the gas engine with rear carb and exhaust, it wasn't very much trouble. Just took my time using my dremel tool with a 1/8 drill bit in it. Very good for cutting fiberglass. Then used a small round sander to smooth the edges. Once in place, I drilled a small guide hole for the remainder of the screws. The fit was very good.
I forgot to mention my ignition module. It fit under the top engine cowl. Making a small hole for the battery lead was just a matter of using aht dremel tool with 1/8 drill pit. Routed out the hole just large enough for go inside the fuse.