A couple questions for those familiar with 99-04

[Mach 1]

I've been out of the stang game for quite a few years, my last being an 93GT which i sold in 2002.

Ive recently aquired a new girlfriend who drives an 02GT, unfortunately shes been letting people work on her car who have no business in doing so, and Im trying to get it straightened out for her.

1- front tires are worn badly on the inside edges. She has mentioned having a "bump steer kit' installed, i thought to prevent tire rubbing, but now she is telling me it was to improve handling and has been creating the tire rubbing. All i see is what looks like additional spacers on the tie rod mounts which look as if they would throw the alignment out. Will removing these spacers remove the problem? She also has what looks like a maximum motorsports adjustable alignment kit on top of the struts. shes running SR wheels, i think around 9.5-10 inches wide, BBK lowering springs, with 245/40/18 on front and 285/35/18 on back. The back tires are wearing in the middle, i believe a combination of over-inflation and the tire being slightly on the wide side for the rim.

2-JLT cold air intake. Is this intake thick, heavy PVC pipe in its original form? I think she traded somebody for a home made knockoff, and it was literally hanging there with no additional mounting support. she doesnt have oem intake, and im thinking replace it, so looking for recommendations CAI kits, not looking to spend a lot, but dont want junk either.

3- Im feeling tons of slop in the drivetrain. its not all the time, but for example, when you release the throttle in a lower gear, unloading the drivetrain, it feels like the universal joints or tranny mount are flexing. Inspected these items and they look good, but i did notice if i turn the driveshaft by hand, i get quite a bit of movement before the rear diff. spins. Is this 'play' normal?

4- it has trick flow upper manifold, lower appears to be oem, BBK 75mm TB, oem exhaust manifolds, bbk X pipe, cat back with flowmasters. This combination doesnt appear good to me, the car doesnt seem to be making 260 oem hp, yet alone seeing any gain. Do headers provide a nice gain in this application? also has 130k miles