Hi, hoping someone can help me. I've been finishing up work on my 1970 Cadillac Eldorado. I've been fixing some last minor details and I noticed my speedometer doesn't light up when the headlights are on and it still doesn't work no matter how I adjust the dimmer switch. I took off the upper dash and pulled out the radio again to get a better look. I replaced the bulbs and it still doesn't work but I did notice a set of Orange, Brown, and Black with White stripe wires that have a connector at the end but I have no idea what it is supposed to be attached to. I couldn't find any wiring diagrams online and I really don't want to buy a shop manual. I've attached 2 pictures of the wires and the connector. Hopefully someone knows where they go or can help me figure out why my speedometer doesn't light up.

Thanks in advance, Frank