03 mustang gt will not start

My stang will not crank over at all when turning over the key. I checked all the fuzes inside and out of the car, It will start up if you jump a wire from the battery to the other small wire on the starter. I have no idea what it be the car only has 45000 miles on it dont really think it be the key switch or the clutch pedal switch. only thing i did was put long tube header's on it. drove fine for 2 days then wash it went down the road about 1 mile park it got back in it then just quit starting. Check all wire connection's to there all good even bought a new battery for any suggestion will be helpfull.:banghead: Its a 5-speed manual

Found out what it was the starter relay switch in the fusze box underneath the hood:rofl: