OK, here are the dimensions I think you will need. These are on repro retainers, but I suspect they are the same dimensions as the OEM pieces.
Largest O.D. without the 'fingers' is 2 3/8"....
Best 'guesstimate' of the O.D. including the fingers is 2 7/8"....
Height is 1 3/16".....
Smallest O.D. is 1 7/8"....
