Ron
On some of your comments you seem right in tune with the job, but then you seem to waffle a bit.

The black hex thing is the ONLY thing to worry about right now. You just use the chisel at a rearward angle to drive the coupler rearward. It's not rocket science. You'll see when you get it off.
It's ONLY hex shaped because the front of the torsion bar is, and the rear part of the control arm is (where the torsion bar engages). They could have made it about any shape they wanted except round, settled on hexagon shaped, maybe it was the cheapest way (probably it) or they paid an engineer somewhere a boat load of money to decide what shape to use, I dunno. It's NOT to attach a wrench to.
As I said, WIS says there are bolts that are supposed to go into the coupler, I suppose with the intend on preventing the coupler from shifting back on the torsion bar on it's own. Someone probably decided that coupler is going NO WHERE when the bar is actually installed on the truck (torsional force).
You won't damage the copler, it's quite thick. I've never had or seen a "real" problem getting the coupler to slide back. Once you do it it'll make perfect sense.
Maybe post a few more pictures for the benefit of others who may need to do this to show how it comes apart.

Gilly

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