Multiple problems. Most likely all related to the OD. From here it looks like you have some more work in store for you. You will probably end up with a really good car for an additional few hundred and a couple of weekends of work.

First some diagnostics BEFORE you e-mail me for more info. Under the OD on the left side, directly under the solenoid is a plug. Remove it and catch the small amount of fluid that drains out. Any container that will hold a quarter cup will do. If the fluid is any shade or has streaks of silver, you need to find another OD. The aluminum sliding member has been ground to bits and it is cheaper to get another used OD than rebuild what you have. ( New sliding member and bearing about $700. Factory rebuilt OD $1400 which is why previous owner sold car. This is wild educated guess on my part).

No OD light. First rectangle to the right of the Odometer reset bar in the center of the cluster. Check fuse 11. If blown, you will have to find where the short is. A complete diagnostics is too long for this forum. E-mail me (dhoberg@kc.rr.com) for the document that will guide you through the circuit step by step.

To help you understand. For a planetary Overdrive system to work, the primary drive has to be able to freewheel during OD mode or remain locked during first set of gears and reverse. The freewheel mode does not allow reverse to occur through the primary drive system. The auxillary drive for reverse relies on friction material which in turn "locks" the planetary gear system. Your OD planetary system is no longer locked which is why you have no reverse. Why it is not locked and what caused it in the first place you are about to find out.

Duane