I recently purchased a 1968 C10 with a 307 and 3 on the tree. The truck has electric overdrive that is currently not working. I have been searching for manuals or web pages, anything to help me get started or find parts to fix it. The previous owner told me that it was a bad solenoid at the rear of the tranny. So far I've had no luck finding any parts or even a diagram of this set up. Please steer me in the right direction!