Certainly a tight fit Vic, and actually the removal would have been the easy part... must have been a b!tch loading her without damaging the aircraft!
As the aircraft were supposedly demolished with explosives by the tankies, I presume they either chopped the rear fuselages (light ply construction) to remove the drums , or left them in situ and simply siphoned the fuel out with hoses.
My own Plan B is to complete the drum, then cut it vertically with the razor saw, leaving only the visible section intact. Can then pop the canopy, cut the remaining section, and (theoretically) remove it ok should the need arise. (Hopefully won't need to though!)