Id forget the limit switch and see if you can just jumper the pins 68 and 71 together and forget the motor resistor, I dont think they monitor the motor current.

I also think that 100+ ohms for a motor is either wrong of there is something else in there, it is too high. 100 ohms at 12 vlots is about 0.080amps, that wont run a hard drive.

Woody