There is a difference in the output shaft seal if the trans fits a dry drive shaft bike, i.e. Para Lever, I think. You can change the seal to suit the drive shaft, if you need to.
All Airheads pre 1981 are long input trannies, whether 4 or 5 speed. All Airheads 1981 and after are short input shafts. There are a number of other changes that accompany the input change so it's best to just stick with what you got. Any GS or G/S bike will automatically be a long input won't it? Did they not start until 1981 or after?
EDIT; I mean G/S and GS will be a short input!!! (I typed wrong)
disston screwed with this post 01-02-2013 at 05:07 PM