1998 Dodge Caravan ABC and service engine lights on; no gau

My 1998 Dodge Grand Caravan with 134500 miles starts just fine. The indicator lights comes on and most of them turn off. However, the ABC light stays on. When I put the van into gear, the service engine light comes on. Also, none of the guages. Speedometer, water temp, rpm, electronic odometer or fuel guage work.
The van shifts just fine and ends up in overdrive just like it is supposed with no lagging, lurching, unusual noises or any other unsavory thing happening. The transmission was rebuilt in 2007 and has been working just fine. The engine runs and sounds normal. I had the clockspring replaced last year according to the recall by a dealer when the horn, cruise control, etc. Quit working.
I get codes 12, 37, 66 and 55 when I run the ignition switch on/off 3 times diagnostic. I dissconnected the battery and left it that way for over 30 minutes. When I reconnected and restarted, I got the same ABC light staying on, the service engine comes on when going into drive and the guages still don't work.
I know 12 is for battery recently disconnected and 55 is for end of codes which are okay codes. My Chilton lists 3 different codes for 37, one of which is park/neutral switch stuck in park which might explain the service engine light coming on when I put the van into drive. The 66 code indicates no CCD message from the Body Control Module (BCM) or the transmission control module (TCM). I have no idea if that would be responsible for what is taking place or if it is even related.
Any ideas? If it is the park/neutral switch, where do I find it. Steering coulumn, under the hood or on the transmission? Where are the BCM and TCM units and can I get to them without special equipment or would it be best to call my mechanic?

Greatly appreaciate your assistance.

Thanks!

Jim L.