Trailer hitch mounting nut repair

[Super77]

IIRC, there are 6 threaded weld-on M12 nuts in the frame rails that receive bolts that hold the trailer hitch assembly. When I removed my hitch assembly, I noticed one of the threaded nuts was stripped out and a smaller diameter bolt had been fished down from inside the frame rail. It's impossible to tighten a nut onto that bolt since the head spins inside the frame rail. I need to fix this before I reattach the trailer hitch. Options:

1) Ream out and tap to M14. I'll have one odd-sized bolt. Quick and secure, but triggers my OCD .
2) Ream out and re-thread with a M12 insert. Same size bolts, but are the inserts capable of high torque?
3) Remove bumper to access the frame rail opening, air-chisel out the stripped nut, tack weld a new one from the outside. Ton of work, but juuust doable.
4) Keep the existing bolt kludge, caulk around it with a blob of JB weld to keep it from spinning.

Thoughts?

 

[hoser]

Flag nut?

 

[Super77]

Flag nut?

Didn’t know it had a name! Yes, I can make this by tacking a thin rod to a nut. Good call.

 

[John McVicker]

I believe you would be fine with any of your 1st 3 choices. But I think me personally…I would go with #1.

 

[Dirt J]

If you go the flag nut route, make sure the nut has a square piece welded to it that will fit inside the frame rail without it spinning. I've attached aftermarket receiver hitches that use those square/rectangular nuts with the stick or flag to position.

Are you sure you can wedge a flathead screwdriver in there to keep the head from spinning while you tighten?

If you plan to remove/install the hitch regularly, I'd go #3.

 

[Super77]

lol this being 'Mud, I assumed all y'all would go for the JB Weld. I'll confess, that's what I did temporarily when I discovered the loose spinning bolt and it's still holding strong