Looks like somebody has been here before, and they might have been drinking too.
The good news, Bob, is that the tube hardly moves at all when depressing the clutch. At most, 1/32", and towards the middle of the car rather than front to back, so that had nothing to do with the adjustment issues. So Mark,
Just kiddn' dood, I'm glad. I would have felt pretty stupid if that was the source of my stage III train wreck.
Tough to make out here, but the hack job involved welding a piece of scrap to the bottom of the tunnel, then to the clutch tube. The creak is coming from the tube edging sideways against the remnants of the original bracket. I'm not sure why they stuck the extra piece of metal in there rather than just re-tacking to the pretty health section of the bracket that is still there. Give added strength I suppose. But it looks like one good bead to secure the whole thing laterally to the braket, and I should be good to go.
Time to get that new MIG welder I got for Christmas out of the box.