As groundforce said, use CA! The instructions tell you to, which means your ARF came with CA hinges, epoxy will NOT hold them. By the way, get CA, not Superglue. The Superglue formulation is not the same as CA and while it may work, I don't trust it.

Many planes have a tank compartement that does not allow the tank to fit completely into the front section. Just push it in as far as it will go, don't force it or you can damage the stopper or fuel lines.

As long as the wings go together with a dihedral brace, and you use 30 minute epoxy to glue the halves together, fiberglassing is not necessary.
Dennis-