Dash lights and not working now

How did you figure out which wires to use? There were likely two lighting wires going to the original radio if it had a digital display. One from the tail lights dimmed the display when the headlights were turned on, and one from the dash lights told the display how much to dim. Many people use an ohm meter to find what they think is a ground wire. Either light wire will measure very low resistance, just like a ground wire, because you're reading through lots of light bulbs to ground.

If any type of Body Computer is involved with the dash lights, it is very possible to not blow a fuse when that wire is grounded. In this case, the lights on the dash should work again after you disconnect the radio. If they still don't work, you may have to look in two places for a blown fuse. There will be a fuse box inside the vehicle and possibly another one under the hood.