I'm new to fords as well.... I've been a GM guy all my life, but I picked up my 89 GT convert this weekend, and it's rained ever since.. but that's besides the point, you're going to get a million responses answering all your questions...
but I'll tell ya this, you spend 1 week just reading all the posts that come across here and you'll be well versed on ford 302s.. everywhere from rear ends to fan clutches...
All those S, A, T Trims are vortech blower models
http://www.vortechsuperchargers.com/units/
The only thing I can say bad about this site, is there's no production figures and available options list for the mustangs, least not that I can find. But the 5.0 in any car came with 225 horse, or so Ford claimed. though alot of people liked the LX cause it was cheaper with the same engine
I;m not going to get into the mods cause I dont know much about moding these EFI engines, I'm a carb guy, my last car was a 72 Olds Cutlass, so I'll let someone else take over... but you mentioned super charging...
there's a bunch of bolt on superchargers for the car, vortech is one company, so is paxton, there's another one out there, i forget the name, that no one on this board seems to care for... but if you wanna learn alot about this car, just go back and read the posts... it doesnt matter if it's not a problem you're having, cause it's good to learn about all the stuff that you can do with the car as well as what to look out for when it does break down...
ok, enough from me
-=as=-