Windshield washer motor

[Swedefish]

Kind of stupid question, but how do I get negative ground to the washer motor on my A-body Cuda?
It runs when I jump a wire from negative on the battery to the housing on the motor.

Had a look in my service manual but it doesn`t say anything.
May be beacause it `s obvious 
Any thoghts on this?
Many thanks

[Chryco Psycho]

usually there is a wire attached to the motor to ground to the washer tank mounting screw , if it is not there you need to make one or buy a new motor from a local parts store

[Swedefish]

Thanks CP
I`ll see if there`s a place to attach the wire.