Glad I could help, PT19.

On my 1/3 scale, there is no room, in the engine compartment, for the ignition or battery. I haven't installed them yet, but I imagine that they will be mounted on the interior side of the firewall.

There's plenty of info about Solartex, on RCU. For scale models, it is my covering of choice. I find it to be easy to apply, and it does not require all the work of, say Koverall. You can paint it with almost anything. I don't even use a primer. My 1/3 SW will be painted, using Rustolem, in quart cans.