Cadillac Repair: Probe Speedometer and Bobbing Headlights, vehicle speed sensor, electronic speedometer

Question
This is a two part question...  I recently bought this Probe LX from an abandoned car auction and after replacing the plugs and wires she runs great. The headlights were 'stuck' up and I noticed that while they would turn on and off they wouldn't go back down. I noticed they were unplugged and upon plugging them in they would immediately begin "blinking" up and down and up and down...I have ordered the Haynes book but have no idea where to begin. I suspect the motors are good as they seem to operate very smoothly and quickly.
Also, the electronic speedometer stays at zero but the tachometer works. I did not notice if the odometer moved or not. Where do I begin to try and fix this.
I have been looking online for two days and have been unsuccessful finding anyone with problems like these. Your help is greatly appreciated, thank you.  

Answer
Hi Bill, The Ford expert must be on vacation or taken his max questions huh? LOL With the headlamps look for a relay in the headlamp circuit. Maybe one of them, GM cars use 3 to control the up/down, is sticking and won't turn the motors off at the end of the travel....As for the speedo look to make sure all the fuses are good. Then check the vehicle speed sensor connector and wires at the transmission to see if they are plugged in and ok. If so then remove the vss from the trans tailshaft where the RH axle goes in at the top and see if the gear is ok. By hooking up a voltmetyer on ac scale and turning the gear the vss should create a higher voltage signal the faster you go. Most times it is the vss and a used one can be gotten at a junk yard which is what my shop does. If that doesn't work then start tracing wires for opens and maybe you have a bad dash or comnputor. Before replaceing them it might be a good idea to have a shop look at it because parts will now get expensive. Good luck. Bill