2003 mustang gt - Header leak

[amio]

I recently installed headers and the driver side has a leak. I've been trying to find a repair shop to tighten it as I don't want to go through a headache again.
But every repair shop is telling me they won't fix it and that I need to call a muffler shop (they won't tighten it either). I'm a little stumped on what to do can anyone lead me in the right direction?

 

[Dark04GT]

Those header bolts are a massive PITA to get to and the stock bolts will just loosen again. That is why nobody wants to touch them. Find a performance shop that does header installs if you need some help. Expect that it might cost you 2-3 hours in labor. Retightening the bolts is a hopeless endeavor, I made the same mistake and within days of having new headers I had a stinky exhaust smelling car - install the permanent solution, have the performance shop install a set of these: https://lmr.com/item/M9432A54/96-04-Mustang-Stage-8-46l-54l-Header-Bolt-Kit