I was about to dismiss these from being a Simplex part as they were mixed in with some other peculiar parts. But the holes lined up with the Wico flywheel.  (that's witherbee ignitor co.)  Upon looking in a manual it turned out they are indeed a Simplex part.  Looked to be NOS as there aren't any bolt marks.  I would imagine they weren't often used as one could definitely get by without it.

Interesting there are two different assembly part numbers.  Might this be the difference of  a two plug coil to a one plug coil?

I have been thinking of an approach of how to go about restoring this bike.  i have decided to photograph every part as I received them.  To have a bunch of photos to refer back to as the restoration goes on.  The manual is very helpful as it has already uncovered the myth of what the little ring was for just behind the seat.  Choke knob! 

So I will just begin at the beginning.  First picture is of the lean release where the original owner paid the bike in full.  Shows matching engine number.  Next pic is a receipt that shows he bought a rod and other parts.  The story is he 'blew a rod in '48!' I guess the receipt proves that.  Other photo shows his payment receipts as he made payments towards owning the bike. 

Lots of pictures of the frame.  Pay close attention to the small clips (or hooks) back near the rear wheel drop-outs Those are what the springs hook on that holds the "hood" in place.  The hood is three sided in that the grill in front of the engine is attached to each side cover.  These hooks are what makes it a 1940.  Kind of strange as it is very clear to what the purchase date was.  ( I have that first payment receipt)

So here's a long story to tell.  Several months back I set out on a quest to locate Lamptester55 that had posted on here 8+ years ago. He owned a 1940 Serviglide. (you can view his posts under that username).  I wanted to buy this bike if at all possible.  Throughout months of searching for him because of his contacts changing over the years the deed was done.  He lived in Dearborn!

This task was then followed by more months of correspondence until, finally,  the decision was made to sell and I was on it!

Rodney is a great guy and I had a great day picking up the bike.  We talked about many things.  He worked for the Ford Motor company for 30 years or so and had many interesting things to say.  Plus he wrote a book.  A pleasure to meet!

That day was a lot to absorb!  It is exciting to know I have a Serviglide in the garage and also that Rodney was the perfect caretaker of it and all the info that came with it for over 46 years!  Makes me the third owner. He worked with the original owners son.  (documented)

A lot to sort through and post but I will start a thread soon. Just wanted to let you all in on what has been going on.

1944  Late G model?

As promised.   And all the way from Newcastle, England!  Feel so lucky to have found this.  Definitely adds insight to what was happening inside Simplex mfg. at the time.

I have the correct spark plug grommets for your Simplex. Say the word and I will send you some!