87SEV6KCPickup

I just had a mechanic replace the rear main seal in my 87 pickup. He had to disconnect and move the transmission to complete this task. Now when I turn the key and the instrument panel lights up while the shift lever is in the park position, the P and the N are both illuminated. When I shift into any position other than P the indicator light for that position is dim and the N is still lit but is also dim.

I had the mechanic disconnect and reconnect the electrical connectors under the Transmission and the problem persists. One other note that may or may not be related to this but it began at the same time as the N light issue, the transmission will not shift into overdrive at any speed or engine temperature.

Within the past 1-2 years the Shift switch as well as the temperature sensor have been replaced, so I find it unlikely that these are the problem, but I am not ruling them out. It does not appear to be a coincidence that these behaviors began immediately when the transmission was moved to replace the seal.

I would greatly appreciate any insight anyone can give into this problem since the shop that replaced the seal is not willing to troubleshoot or fix this problem.