You should get a kit and start the project when you have plenty of time to do it right. You will need to have a wire attached to you battery, so running the wire underneath the vehicle in a neat, safe way so it won't get caught on anything, takes a while. You will also need to ground everything. You should have an opening in the rear inside by the lights, you can put everything in there and punch a hole through the floor inside it. This way you won't cook your system on the dash.
I wonder were that dirt road goes?
'89 YJ 4 banger all stock, replacing all the worn out guts first, 97 grand cherokee limited