Exhaust Leak Problem

Ok so the latest in my mustang problems is a pretty bad exhaust leak. It almost sounds like its either the passanger side header or h pipe.The only part of the whole system that is fsctory are the headers. Are they prone to failure after awhile? Is there a certain spot I should look? I poped the hood and it ddoesn't sound like it could be a gasket and ir sounds like its more under the car. The h pipe and cat back is aftermarket no cats. Its not welded up there either. Could it be where the header connects to the h pipe? My cars also lowered and therws a few dings and dents throuout the system. It sounds like a pretty big leak completly changed the tone of the exhaust and it sound like ass. Almsot embarassing lol

I'm gonna get under there today and see what's going on its def coming from pass side header h pipe area. Maybe this is my excuse to get a new exhasut system. Anyways I want headers but don't know what's good to look for like size shorty long tubes unequal its all new to me. I'm also going to get a new x pipe. I have an h now I figured its time to switch. And I don't know what cat back I have either so ill get something soon enough. But now its headers and x pipe any suggestions?

I figured it out. The h pipe is rotted out at the connection to the headers. So I need a new mid pipe. And while I'm at I will do the headers since there still stock. I also found out that I have a Mac catback.