If your "buddy" capped all the penetrations in the fuel tank, then ask him to explain and demonstrate how he vented the system, both for normal operation and filling the tank with the fuel nozzle at the fuel station!
Simply filling any Scout II (or s80/s800 for that matter) is a major bitch to both make it take fuel, and too keep the nozzle from clicking off early. Even more so with the vapor recovery dispensing systems found throughout kali and in many other states. That is because the filler neck vent arrangement is shit as originally designed.
It takes very careful fuel nozzle manipulation to keep gasoline off the paintwork on the fender.