Need some steering column shifter repair advice

[Anthony Fremont]

My steering works fine, no squeaks in the column and it turns around smooth as silk. OTOH, the column shifter (powerglide) won't budge. It's not the tranny or linkage, that all works fine when you unclamp the linkage rod. It's something in the column keeping it from moving. It's like it is rusted solid in place, no play or movement at all of the lever or the linkage arm at the other end. I've got to fix this to get it inspected, and I don't want to install a floor shifter.

It's currently stuck in "D", not that it matters since the safety switch is bypassed and backup lights are the least of my worries. Any ideas how I should attack this problem? It's a pain opening the hood when you need to change directions.