Is the 7/16 wrench a design with a closed 6 or 12 point circle at one end?

My HF video boroscope has been well worth the sale price i bought it for, but its small camera head is still 9 mm in diameter, and it sounds like the clearances might be tighter than 9/25 of an inch?

If you get a wire that will touch the wrench, you might try two part epoxy. For it to set up the two chemical components must touch and mix some.

If you can get the epoxy chemical on one wire end, and then maneuver the wire to coat a spot on the wrench, then take an identical second wire with the chemical hardener on it and manuever its end to touch the wrench where the two chemicals can be left alone for the time to harden.

There is also glue that sets up only after Ultra Violet light is shined on it.

Good luck.