Why are you doubting yourself Jonesy? This is some conscise and acurate infromation.
Your Images clearly show all the variants as we discussed in a prior posts.
The main point is it lists ALL the variations and what models they predominantly belonged to smile

Additional attention can be placed on the model 3 ring style,as on many model 3 Bases there are 3 holes in the exact postions the 3 hoops sit. Ill post an image of what I mean,as maybee they are the locators for the hoops.:)

I will post an Image of the Early style and this will complete the the known Varaints.
I think its safe to assume as you said,
1:Roto 2 2a 4 Bolt on clamps.
2:The ring style for the model 3 appears the earlier
3:The 1 and 2 tabs with bolt on clamps for later Utilities and Specials,
4:And the Model 4 Auto.
Some Rings may have also been interchangeable on a few models,just being of slightly different design,but still carried over.

I think this is pretty close to accurate and a well presented and Informed post! Any other variants can be added any time in the future...Great job Jonesy..