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imp:
Get a 3 position double pole, double throw switch..(6 contacts)
Wire the window motor to the center wiper, power on the left contact, ground on the right contact...
Then bring power from the fuse to the top left contact, ground to the top right contact, (power and ground to center wiper when the switch is pushed up) This will be "window up"...
Then from the top contacts make two jumpers to the bottom contacts in an "X" pattern, so that power is on the right contact, and ground is on the left contact, this reverses the motor, and serves as "window down"..
BE sure the center position is "OFF" or the window will always be running in one direction or the other..(up--off--down).
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