I picked a seal that fit and made the housing for it just as Chankly suggested. Just bolted it on as I remember, but I am foggy on the seal and housing. I made my own inner primary plate and maybe that is why I did not have to machine anything. I don't specifically remember why I used four holes, but it does not look like too many.
The hardened spacer for the Comet is E216. That is the rough one that is not for use with a seal. E216/1 is the ground spacer for use with the seal.
I think I continued using the seal, but I went to a sealed bearing on the primary: MS-10-2RS. This is sealed inside and out. The bearing house convinced me to run it as is with both seals. It has been running every season for 8, which I think of as success.
After I installed the front sprocket and mounted the belt, I had to pull it apart and put a shim against E216/1 so the sprocket moved out a hair. The belt need a bit of centering on the clutch.
Of course, the Newby fits inside the Comet primary also. The lock wire is not a bad idea. That is 1/4" plate used for the inner primary. The foot rest and transmission plates are 3/8".
David