I have a 1977 Ford F150 351m engine. I am having difficulty installing a new radio. Not sure of the wiring. The diagrams dont offer much help I you dont know how to read them. I am trying to install a stock Honda stereo into my truck. I have the harness or adapter for it. Just don't know which wires I am supposed to hook up. The wiring in my truck is so messed up. Can somebody help?

 

Did you try looking up a wiring schematic for the radio so you know what wires are for what? You'll need you positive power and negative then your speaker wires pos and neg. you can run the pos power to your fuse box to a connection that has full time power. Check it with your key off and see which fuse has power with a test light and use that or you can always run a positive to your battery through the firewall or a wire that has constant power from your battery with the key off. This way you will be able to have you stereo running without your truck on and it will also keep your memory for preset stations. Then run two lines to each of your speakers for power. Cutting a hole in your dash is not always fun!

 

The OEM radio was powered by a GREEN 2-terminal pigtail. YELLOW with a BLACK stripe is switched power, BLUE with RED stripe is dash illumination. Do not mistake the BLUE with RED stripe wire for ground. The OEM radio grounded through its mounting chassis. The speakers were connected over a separate pigtail.

Ok I looked behind the glove box and found a connection the goes off the green and yellow. GREEN with YELLOW stripe wiring is hot-at-all-times power for the courtesy lamp circuit. Use that. There is a 3-connector pigtail behind the glove box (which also goes on to power the cigarette lighter).

It's not the stock radio wire because the stock radio didn't need hot-at-all-times power (EXCEPT the factory digital AM radio for clock memory).
solid black—power blue with red stripe--dial light black with gray dashes—ground orange with green dashes--right speaker white with green dashes--left speaker
Assuming an AM/FM stereo and stock wiring harness'.
Purple is ground, right speaker is white and left speaker is orange.