Yes, will be attempting that today, in fact. If you press the switch and your dome lights dim, switch should be OK. Switching just the motor, it's 2 bolts and one hole to drill. Can unplug the motor and apply 12 volts to the plug to test it..On my 98 XLT 4X4 BUT apparently on the 94 you have to fix the regulator in place or it will spring on you hazardously, if memory serves me. Check this forum, quite a lot of discussion on the subject
UPDATE: Unfortunately the used OEM motor I got from Ebay, doesn't run either! Will be taking it apart to see if it the the easily rebuilt nylon bearings that is the problem...