question on top motor

I've pickup 2 motors both like new one from a 89 sebring and one from 2001 mustang, both work the top when I hook power to one wire and ground the other or reverse it and toip goes down.

Problem is and maybe you know is when hooked up to switch there no ground on motor has anyone else over come this...

Junk yard motor $23.00 vs new mopar $220

I'm cheap