Parking Brake Cable Equalizer Adjustment --1998 GMC Sonoma (same as Chevy S-10)

[windswept4]

The parking brake cable equalizer on my 1998 GMC Sonoma (same as the Chev S-10) is under the driver door and it has a 12 MM hex nut on the threaded end of the cable that continues on to one of the rear wheels. I grip, with vice grips, the square stock of the brake cable at the point where the threading begins and I use a 12 MM open end wrench on the hex nut. With that excellent leverage and grip on the cable and the nut, the nut won't break loose and turn on the threading. It's been soaking in PB Blaster for 3 days now. Should I heat the nut with MAPP gas until red hot, quench quickly in cold water and try turning the nut again? Or is there an easier way to get that 12 MM adjusting nut to turn?

 

[windswept4]

Here's a link to a photo of the equalizer and the adjusting nut. The parking brake cables lead to the right to the rear parking brake shoes. The elongated nut is the 12 MM adjusting nut; and it should spin to the right or to the left of the threaded cable. Gyazo