When I first got my 64 SDV about 8 years ago, the power seat made noise but didn't go anywhere. I promptly read up on it and proceeded to take the seat transmission out to clean and re-lubricate it. I used vaseline and maybe too much of it because for the last year or so the seat was temperamental again. Especially in cold weather. It is worth mentioning that you can try using a hair dryer on the seat transmission if yours does not work, but the motor makes noise. If it works in that circumstance it means the transmission solenoids and rods are gummed up-and will likely respond well to cleaning and re-lubricating. 

After removing the rear seat cushion for wiggle room, I unbolted and laid the seat backwards thereby exposing the seat motor and transmission. Unbolting and cleaning went about as expected.  The only thing I did differently this time is I used white lithium grease instead of vaseline. Also I crocus-clothed out all passageways and rods. The seat now works perfectly again.

On another note, I purchased a Delco AC Comfort Control tester that will tell me which of my ac components requires replacement. I am eager to find out the results, but wil wait till I stop hurting from this adventure.