Door lock motors

my alarm has recently stopped working resulting in me not being able to lock or unlock my doors, as the central locking was not a standard fitment.

What i want to do is wire up the passenger door lock motor to a switch on the dash(door pins were removed and will be a nightmare to refit as it was previously delocked.). i can open drivers door with key.

the problem is the motor has only two wires too and from the motor, there is no ground wire.

to lock it i have to ground one wire and apply 12v to the other

to unlock i have to reverse it 12v to the previously ground wire and ground the previously live wire.

(the alarm used to control the lock motors  when it was armed and disarmed)

can anyone tell me how it is possible to wire it up to a toggle switch where it is normaly off, push one way to open and the other way to close.  i know how to do it if they shared a common earth, but because they have to alternate polarity between the two wires i'm stuck.

alternatively could i use the drivers side motor as a switch.  the drivers side door motor has two wires from the motor and three seperate wires one an earth wire not conected to the motor itself. when the lock is in the up position one wire forms a conection with an earth wire and when moved down the other wire forms a conection with the earth.

any help would be apreciated.

A DPDT Toggle would work.  Like the old Universal Power Antennea switches.
Otherwise  a SPDT switch would work using 2 Relays.
If your local Electronics shop doesn't have it, check with Radio Shack