Dave, I have a feeling I'll be calling on you for advice before it's over. Worst case, you'll have another 123 chassis on your doorstep
Meanwhile: the yoke has the typical rotted plastic shell. I was thinking today of something that has the potential to be a great solution-if I could find a defective 21" color yoke from another model, maybe I could transfer the plastic? I've taken yokes apart to junk them and sometimes it just involves removing a screw or two. I haven't compared the two styles side by side; who knows, maybe I have some oddball yoke around here that I could look at. If somebody has a dud sitting around, let me know.