HELP please: What to do with a situation NOT in the service manual, NOT in parts list etc?

I am quite stuck, and in need of some wisdom.

CONTEXT

• 2011 Gen3 Prius. I am replacing the sway bar bushings (see Mendel's shared PDF, pp 37-38)
• To remove the LH bushing requires (according to service manual) removing the LH Front Lower Suspension Arm (attached to the Front Suspension Crossmember), and the Front Suspension Member Front Brace, which is held on by four bolts.

A Not-So-Tiny Problem

• Unlike other generations of Prii, this one isn't as simple as described.
• The right side, I didn't even need to remove the control/suspension arm, just the "Brace."
• The left side? Auuugh! One of the four bolts is NOT held in by the metal it bolts to. It has a hidden nut.
• Please see photos below...

I assumed I could access the nut by removing the LH control/suspension arm. WRONG.

• Said nut is inside the Front Suspension Crossmember!!!
• Said nut is NOT listed in the parts diagrams for my car
• Nor is there any explanation of how to grip it to install or remove the bolt that holds the 'brace' for the sway bar bushing.

I need ideas, experienced input, wisdom.

• How can this be? (My guess: perhaps the nut was originally tack-welded in place?)
• Any ideas how to hold the nut through the lower suspension arm bolt hole, for removing and later re-installing the wayward front brace bolt?
• Is there any recourse with Toyota for such a hare-brained design???

In the photo:

• Above: the front suspension crossmember...
  • With slot for the control arm bushing...
  • And holes for the control arm bushing bolt, inserted on left.
  • The hole is 14.5 mm
• Below: you're looking at the Front Suspension Member Front Brace, held in place by just one bolt, aiming (upward) into the bottom of the Front Suspension Crossmember
• (Off to the right is the sway bar)

Photo below: taken with USB cam inserted into the 14mm suspension arm bolt hole in the side of the front suspension crossmember. You're looking at a 17mm nut.


I am stumped at this point.

 

Great questions...

Yes, absolutely spins. And yes, confirmed it is loose in there.

I kinda assumed I need to remove more stuff... but don't see what can be removed that would help: that big hunk of metal is all one part on a Prius! It is the Front Suspension Crossmember.

Yes, I have a powerful impact gun. My next step is going to be to use the bolt hole to squirt some penetrating oil on the nut and wait a while for it to work.

I do own a right-angle crowbar. Not sure I can get it to fit in there, but something like that may help.

My other thought is to use the magic of modern chemistry: perhaps there's a super strong adhesive I can squirt in there to hold the nut... or perhaps to fill the space between the nut and the side of the metal box, and keep it from turning?

Pretty sure I could:

• Pull down on the bolt and spin, causing the nut to grind a bit and create a relatively smooth mating surface between the nut and box
• squirt anti-adhesive into the bolt hole to protect the bolt-nut connection (grease?)
• then squirt a thin super-strong (epoxyish?) adhesive around the outer edge of the nut, using capillary action to suck it into the mating metal-metal surface. Idealized result: nut is bonded to the box, and bolt is free to turn...

Yeah, in my dreams