Mr. Barkley, interested others ...
Unfortunately, after all the work, the effort I put into the conversion, I finally gave up. Reason?
After over a month of work, just as I was starting the final assembly of the belt drive system I'd designed, a friend pointed me to an add in a local newspaper for a Craftsman cast iron top table saw for $50! Less than four hours after she called me about the ad, the saw was sitting in my new shop. It was a nearly ruined disaster of a saw. Both arbor bearings out of the housing (somehow, it still wanted to run!), the vibration and noise rendering it unusable, and covered in rust. Also, both table extensions on the saw were cracked at the inside rear corners. But, guess what? Both the extensions on the flex drive unit were in perfect condition, unbroken. Sooo ... easy swap.
A week later, all the rust had been cleaned off, the top polished and waxed to shiny cast iron, it had been completely disassembled, then re-built with two new parts (bearings and retainers), and has run utterly perfectly since. I've been overjoyed with the precision, and ease of use. I've read so many complaints about the fence that came with the saw, yet I've had zero problems with it, for my purposes. It's accurate enough that once calibrated and locked down, I use the cutting gauge to make most cuts with. The most serious criticism/complaint I have is that Sears 'motor-mount'. In my opinion, its by far the weakest part of the saw. Terrible, weak, really bad design.
The Flexdrive unit that I spent soo much time and effort on, alas, is now sitting in pieces, in my outdoor storage shed. Have the motor in my shop however, nice and dry. I spent at least a hundred dollars having parts fabricated, and untold hours trying to reconfigure the thing. I'm not one to give up easily, but it just didn't make sense to continue, especially since I now have a perfectly gorgeous, polished, working saw ... for about a week's easy effort.
One good thing that did fall-out of all that 'wasted' work, was that I learned a hell of a lot about how table saws work, and how to repair them, when I knew next to nothing when I started all that. And some of that knowledge went into the rebuild of the belt drive.
By the way, the Sears Model Number, Mr. Barkley, on the flexdrive I have is: 113.241691
I'm sure there are other numbers for slightly different units, or older or newer models of the same basic unit, but my guess is that this number would at least get you a flexdrive cable, if you still needed it. Since that drive cable was definitely an out-sourced component, I'd bet Sears used the same one on all of them.
And, you seem to have had the same difficulties with the Flexdrive unit that others have had. Though, in some applications, the saw does work well--enough.
Finally, I have to add, my strong recommendation to change out the belting on any power tool, to the Fenner belting. I had to order the belting from Grainger and that took a couple of days. I also replaced both sheaves with cast iron units instead of the fonky aluminum ones that came on the saw originally. I couldn't believe the difference. And, yes, I swear this is true, I was able to balance a penny(!) on edge on this saw, and it remained standing, through startup, run, and shutdown ... almost. It fell over, finally, just as the blade turned, quivered, through those last few revolutions at shutdown.
Thanks to Woodworking Forum here, for all the help, and providing the channel to get so much great input on this 'project'. Greatly appreciated.
Best to all ... and thank you all for the responses.