Need help with power seat operations

[N2BUICK]

Looking for someone on the site that has first hand knowledge of troubleshooting the driver power seat.
I have a power seat track I'll be selling to a board member if I can guarantee it is working properly.
I replaced the cracked housing some time ago. I put 12v to the unit and got basic operations. Before I boxed this item and finalized the deal, I decided to recheck the operations. Found all was good except the motor end of the assembly would not retract (go down) after extending up.
Oddly I can get it to go down when I reverse the polarity.
The switch im using i something I had laying around, maybe from an 86 GN?
The seat track is from a 87GN, but the switch looks different. It plugged in and works, I didn't suspect a problem until now.
Any ideas on pinning down the issue?

 

[pacecarta]

plastic gear box is 86 and earlier , single motor
the 87 up has 3 motors, no gear box
you need the correct 86 switch for the track you have

 

[N2BUICK]

Thank you sir, i knew someone would recognize the issue. The motor and trans are good just needs the correct switch.