Hello Everyone, hope someone can help me out!

On my Ranchero im having trouble getting my wipers working. It is a single speed motor and dash switch. My old motor upon disassembly smelled burnt so i purchased a new rebuilt one. I installed the new motor and nothing. So i got out my test light to see if im getting power to the 3 wire plug. Heres what i got:



With the key on, wiper switch off and the motor unplugged from the car I get a constant 12 volts from the Green wire (the one in the middle). When I turn the switch on the dash on, I get power on the Black wire, and nothing on the orange wire no matter what i do. Shouldn't the Black be the ground wire? Also there is a longer black wire that slips on a terminal which is on the gearbox (I assume) that appears to do nothing. It isn't a ground because i tested it with my light tester with the tester connected to the pos terminal on the battery and it didn't light up.

Heres a pic of that terminal:

Heres a picture of the plug on the motor side:


If I connect the light tester to the pos terminal on the battery to check a ground, I get nothing on the single black wire, light on the black wire on the plug, and light on the other two wires! Im confused and starting to get frustrated!!! If it seems like the wiring is totally screwed up i am not against wiring it to a toggle switch under the dash just so they will work, but i want the park feature to work right! Also, if someone can point me to a good wiring diagram that would be great. I hope someone can help me figure this out!!!

Thanks in advance!
Alex