It looks to be fairly complete--I dont see a seat though.  The serial # 304857 should be a 1939 model.  They used a Continental engine.  There was a 5 gear &amp; a 3 gear--the 5 gear engine was earlier.  As for getting it inside.  If it's stuck &amp; been outside for many years already it may not matter.  It all depends what is open to the elements &amp; how your climate is.  One thing about getting it inside is that most of the deterioration stops.