I recently put a cd reciever in my 74 and ran both the hot wire and the ignition hot wire directly to the fuse box. Odds are you have places to "plug" into the fron of the fuse panel for applications like this. If you aren't sure, get a cheap continuity tester light. You can use it to make sure you get an always hot and ingition only hot line from the fuse box. You can just tap directly into a place where there is an existing fuse, but make sure you tap in on the correct side of the fuse. (the side that is hot and not the side the fuse itself supplies. The ground wire you can just run to any good metal ground near the radio assuming you still have the metal tub. If not, run a wire to the nearest ground location if you have a fiberglass tub. If I was confusing, email with what you didn't get.