Brunito
I have the tank just braced up with foam rubber and I have the servo tray screwed down insted of glued because you can't get the tank out if you ever need to with the servo tray in.
As far as the pushrod for the throttle,just drilled the hole in the firewall and ran the rod back to the servo on the same side as the throttle arm on the engine.(use the thin wire and plastic tube they give you)
I also put the battery pack under the fuel tank.