Mustang fuse problem!

Yes take it back and tell that a hole you had rebuilding it to fix it but if you cant start at the source the only logical place to look would be what you have had done last right b4 the prob started crawl under there and look for burnt wires loose hanging wires anything out of the ordinary then if you dont see anything start looking behind the dash pull the radio out look back in there when a fuse blows its because there is a short in the circuit either to Ground or a turn to turn short there is only 3 electrical problems one could ever run into thats opens shorts and grounds so its pretty simple if you know a little more about electricity take a look in a book it will blow your mind :D thats a good start anyway pm me if you need more help