OK, longer post here. Here are the components and assembly of the drive and fork base...
First the main ring that everything attaches to:
You can see the spring attached in the wrong place. You also see the underside of the slo-mo gear with the recess that fits onto the main ring.
Next are the pieces that attached the RA SC:
The SC goes onto the main ring. Then the spring goes on top of the SC. Then the slo-mo gear goes on top of that. Extra points if you have 3 hands. It would make assembly easier because you have to hold the slo-mo gear in place against the pressure of the spring (which I "enhanced" with some small bends). While holding it all together, you have to thread some socket head cap screws up through the main ring, into the slo-mo gear. The spring provides pressure against the SC to hold it in place once you set the SC to the initial coordinates.
Next is all this assembled:
Now you can see the underside of the main ring with the SC assembly completed:
The gear simply slips over the main ring. It's a really snug fit. Excellent machining. Because it's a snug fit, you have to align the bolt holes up very precisely. You can see how I used a flashlight to align them. I also found out the threads were 8-32, so I used some extra 8-32 bolts to ensure the alignment was correct enough to allow it all to bolt together.
Here is everything attached to the main ring:
And finally, the main ring attached to the hub:
The main ring simply sets upon the hub in a machined recess. The gold colored bit is the clutch and is simply metal on metal, although there is a nylon screw for tension adjustment. The four screws you see on the clutch are the ones that were really loose and two fell out, allowing the fork assembly to crash into the worm, damaging the RA SC. I chased the threads with a tap and used 1" instead of the factory 7/8" machine screws with a little reversible thread lock. Should be good to go for years now.
The four bolts actually bolt into the fork assembly piece. When this is done, it all slides over the RA shaft (as illustrated in one of the earlier photos). It's held in place with a washer and machine screw. Put the cap over the screw and bolt the forks on and you're done (at least one fork must be bolted to the OTA or you won't be able to get the OTA on).
Here are the socket head cap screws I mentioned. I just need to get longer ones (the original hex heads are back in place for now).