Just to close this thread out:

FYI the shelf above the ashtray comes out easily. Just pry off the plastic around the cig lighter to reveal 2 phillips head screws. Remove the screws and slide out the tray. It will give you the space you need to get at the fuse box and relays.

1. The OD solenoid may not have been the problem, but I swapped it out with a better conditioned one from the boneyard (US$11)
2. The OD relay (located behind fuses) was fried. Tell tale heat marks were on the outside and when I looked at the solders under a microscope I saw 3 solders were cracked. I got 2 OD relays from the boneyard (US$12). Drilling vent holes in the relay case (pull off case first!) may help with heat issues in warm climates.
3. The Brickboard FAQ was PRICELESS as I was tracking down this problem.

So if anyone experiences the "Stuck in 3rd gear" or "OD arrow light always on", then check your OD relay first, then check the wiring and the solenoid. LASTLY check your tranny. These trannys are well built.

DON'T take it to a transmission shop and let them pawn off a tranny on you for lots of $$$$.