I hate surprises....
 

I hate surprises.

I removed the interior from the Mustang and found where the left front stud for the drivers seat had been welded resulting in some of the wiring harness melting:

I also found a split in the drivers floor where it meets the transmission hump, and I have no idea why there are holes in the floor in front of where that stud was welded.

Based on the tear and the seat stud re-welding, I'd say to look for front end suspension damage too, possibly on the passenger side of the car. The car must have had a severe cross body torsional flex occur (I have some other big words too but it got twisted is basically what looks to have happened). If it was a hard enough hit you should see some buckling in the framework metal on the front end possibly from running something over or going off road. These cars do not have a completely rigid chassis (that's why those aftermarket frame rail connectors and the shock tower connectors are available) and the flex can occur if there is a severe enough bump on one of the front wheels at speed causing the twisting motion to occur and overloading the floor pan and causing that rip which also probably tore the seat bolt stud out too.

That's some low-bid repair work right there....broke the seat, got a leak, weld it more, drill some holes! :yes:

Seriously, we've seen much worse, but don't let it get you too down. It's all correctable.

that repair is a very common one for a car that saw over 100k miles of police service. Especially if it was driven by a person of substantial stature. I have several cars with that repair done. It is normally caused by the drivier getting in and out over and over and the flex of the stud support over time.

The crack in the floor near the hump is also common do to the subframe design and flexing of the car under hard acceleration.

nothing but wear and tear on the old girl. Don't let it discourage you. I own and have seen/repaired worse. :)

Is the crack something that can just be hit with a mig welder?

You could, but I think that reinforcing it with a patch panel is a better idea.

Bernie can help you with that question, though....he knows way more about welding than I.

Good point.

I know all about surprises and repairing low bid so called "repair" work. Like everyone said, don't let it get you down because these cars are far from perfect and from what I have seen thise issues are repairable. I came close to just selling mine a couple times in the last couple weeks but just fix it right and you will feel better about it. Mine has been to the frame shop to straighten out the front core support and shock towers as well as replacing both inner fender aprons. I have so much money in my car by now but I am past the point of no return but it will be right and look good when it is done.

I agree, these defects are repairable & everyone has their own idea as to how they should be repaired. They are as previously mentioned very common. I worked at a FLM dealership from 1982-96. These cracks started showing up in the early 80's. I repaired several at the dealership. That's what prompted the reinforcements. Another contributing factor along with the owners stature is how the owner gets into the car. Alot of people "fall" into the car to get in. Then they push against the seat back to straighten themselves up putting stress on the front seat bolts and of course causing the famous seat back "twist". The repair on your car is one of the better looking ones. I've seen some that looked like someone used an arc welder to do the job. I had a low mileage 91 GT once that the previous owner just kept dumping oil dry on the floor to soak up the water leaking in because of the cracks in the floor. When the car makers went to the HSLA steel is when this kind of thing really started showing up. For all the hard use these cars get in service and the abuse they get in civilian life, they hold up very well. Doug