Well - since Rohan mentioned my name ... the Rex generator
as used on 1915 and 1916 models.  The GE generator used on
1918 and 1919 models.  1917 used something else (not sure
what).  The Rex armature had 3/8 inch shafts and the GE
generator had 1/2 inch shafts (if anyone has a GE armature
laying around I have a friend that needs one to complete
the generator for his 1918).
  I believe the generator setup on eBay is for a 1915 given
that the cover has no provision to mount an oil pump ...
Perry

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The 1918 and 1919 hens used a GEC genny setup that looks
somewhat like this earlier Rex arrangenment. (As Perry
emailed to advise). Ross's bike has what looks to be a Rex
setup because he is using an earlier engine in his 1919...?

Cheers,
Rohan.

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Hello all, if you look on this site at "other Hendersons"
then Ross Weymouths 1919 Hen , you will see this installed
on his 1917/19 bike. A friend of mine has a similar set up
on his 1919 Henderson, regards ,Ken