Too late -- already cut (that's why I said "Oh well"). Opening was pretty thoroughly chewed by loose cable windings spinning around in there -- remember, broke at 80 mph. But deep inside pocket was still OK (discovered after cut off). Oh well. Purpose of square drive is so you can just slip disc onto cable end yet still grip to spin. Square shape, triangular, hex, whatever -- you just need sharp angles to grip. I will rotate my modified disc down threads until snug, then lock in place with fan washer/nut/jamb nut combo. Car's already been run like this. Holds excellent. That's what broke previous attempted repair -- was having to use some of splicing spring as cable itself (longest #8 threads in town are 2.5" bolts. Not quite long enough to replace damaged cable -- remember, was repair #2, so cable cut even shorter -- and still protude through wheel disc). Snapped spring between solder joints (good news is silver solder holds excellent to steel). Didn't help that right angle gears were re-lubed with axle grease (too heavy. Will flush out and replace with gear oil). 3 foot stick of #8 rod won't have that problem -- entire length of short splicing spring will be soldered. Need to use spring for splice because remaining cable and #8 threads are very close in diameter, but not exact. Spring of course expands to accomodate. Weak link in my setup will still be threaded plastic wheel disc. Everything else is steel (I think casing is white metal). Bill Robertson #5939 (tach Xref's taped to dash -- let's hit the road...)