The spool pin is supposed to be in the middle hole. Some 201s had plates and some didn't. There are a couple of threads that show the differences and tells about some of the models of 201s
201-2 and 201K
Why two threaded spool pin holes on a 201? Revisited.
It is a long time since I had my 201 out so don't remember how it was attached.
Janey - Neat people never make the exciting discoveries I do.