Any chance you are having a electric issue inside the column that is causing heat to build up? How are your turn signals/flashers/ignition/horn, etc working? On these old systems things can get pretty hot without tripping any fuses.
just another avenue to consider!
-Jon
70 challenger convertible. 340/5 speed. blown, intercooled, efi, blah blah blah
71 valiant scamp 318/A833OD/AC/PS
00 dakota RC 4.7L 5 spd autoX'r. SRT10/T56 swap in process
73 W200 Power wagon, PTO winch, 4 spd
