Hey guys the model is made by ARC Modelfly sorry for not including the full title. Right the whole plane is made of some kind of plastic not sure what? The firewall doesn't have a + on it. There was 3 dimples which you drill through for the mounting screws. There is a motor mount ring which is glued on the opposite side of the firewall it has 3 nuts on it which line up with the holes i previously drilled. there is a engine mount which came with the kit this also has the 3 holes so the whole assembly secures together with 3 bolts which fasten through the motor mount ring on the inside of the fuse. The engine mount can only be mounted 1 way due to the large hole cut in the right handside of the fuse for the engine to stick out. so its just a case of figuring out how far along the mount do i position the engine. Ofcourse the spinner has to clear the opening but how much of a gap should it be? The instructions for the kit are not the best in the world the pics are way to small can't figure out what half of them are.