Wiper motor

[ruudw]

I've got 2 windscreen wiper motors front and rear from a mk1 Croma, and i want to use the for something else but haven't got an idea how to connect it to my battery.
I tried to ground het motor but couldn't find a suitable place.
And I don't know witch wire is the + wire.

Thanks in advance.

 

[ruudw]

I tried to sand down the thing that's attached to the motor itself an put (-) on there and tried to connect every cable to (+) but nothing happened, so it probably has a (-) cable as well?