Perhaps you could make a few jumper wires so you can play with the seat while it's still out of the car.

With a wiring diagram, you could figure out which terminals go to which motors on the seat, and you could apply voltage manually to move the seat while it's still on your bench.......

__________________
-tp


1990 300SE "Corinne"- 145k daily driver - street modified differential - PARTING OUT OR SELLING SOON - PORTLAND OR. AREA - PM ME FOR DETAILS
1988 560SEL "Gunther"- 190K passes anything except a gas station
1997 S420 - 265k just bought it with a rebuilt trans. Lovely condition