Controller - $300
Motor - From old golfcart ($600 in store)
Wire - $20
Misc nuts/bolts - Already had them ($30 in store)
Contactor - $25
Diode and Resistor - $10
Sprocket - $35
Aluminum Plate and Bar - Already had in my garage.
Misc stuff that I had - $10-50
Step 1: Motor
Type: Series Wound DC Motor
Max Current: 300A
Cont. Current: 100A
Max HP: 15
Cont. HP: 5
It was pretty rusted up and the pulley that was on it was a pain to remove. I took the motor apart and cleaned the dirt out of the coils, brushes and also greased the bearings.
Step 2: Motor Mount and Sprocket
I ended up buying a standard 1/2" 9 tooth sprocket and machining the inside out on a lathe, to a taper that would fit on the motor shaft.
The mounting plate consists of a 1/4" aluminum plate bolted to the frame, with a 2x1 piece of aluminum bolted to the back of the plate like a clamp to prevent the plate from flexing under the torque of the motor (300A makes an amazing amount of torque on a Series Wound motor).
If your wondering what the 2x4 piece of wood is for, I found out that the steel motor mount that was welded to the motor was not strong enough as the motor is designed for the plate to be bolted to the front with the shaft going through the plate. I didn't realize this until i took it out for a test run and it flexed so much that the chain would slip over the sprocket.