trans question

Is there a long tailshaft and short tailshaft 904 trans?

I ask cause I have what I am assuming ( just bought truck minutes ago and its dark now outside ) a long bed ( assuming long tailshaft ) 73 slant truck with a 904 trans that is shot but have a spare short bed ( short tailshaft ) slant truck ( 1983 ) that prob. has a good 904 trans in it that Id like to use.

Never attempted a tailshaft swap, how much of a pain in the butt is that or would I be better off having a drivehshaft lengthened to make up the difference?

EDIT: Yep crawled under there and parts truck tailshaft is approx 15 inches and new truck is approx 18 inches give or take on both