The movie was called Road Raiders (I think) and I remember watching it as a kid. If memory serves (and bear in mind I likely didn't 'get it' at the time), a group of misfits is in a C-47 that crashes somewhere in Asia. There were two huge guys I remember being chained together so I'm not convinced these were entirely pleasant misfits. Anyways the Japanese troops are closing in fast so they all flee to some hiding place somewhere, possibly a church. For whatever reason they can't hide there forever so their search for a means of escape takes them to some abandoned hangar/shed/garage/barn/whatever that happens to be full of abandoned American airplanes, cars and trucks. Cue the A-Team music (probably) and one sweet, welding-filled montage later these truck chassis with airplane fuselages (and awesome fighter plane engines and guns inside!) come rolling out. The Auburn had an enclosed turret of some sort where you'd normally find a boat tail, BTW. So out they come, shoot some stuff up while the leader of this rag-tag team shows the resident Japanese General (or whatever) how cool he is, probably while smoking a cigar, cue the excessive explosions left and right, then drive right up onto a waiting barge to make your ultimate three and a half knot escape up the river. I think there was even a busload of orphans they rescued while they were at it. Oh yeah, some cheesy love interest crammed in too but I'll admit I was only in it for the airplanes.
I'm positive this is the IMDB listing for it but they differ on their synopsis:
http://www.imdb.com/title/tt0098207/-Tim