I have a 1992 Camry LE V6

Will my friend's cat-back exhaust from his 94 4cyl fit my car?

If I buy a generic performance muffler, does it have to be made specifically for a V6?

Is there any way to clear my cloudy headlight lenses without replacing them?

Where can I get a high output alternator since my stock one isn't up to handling my stereo?

Any help will be appreciated.