Headers / muffler choices....

Post this in the Tech section and you will probably get more responses, just an idea

No need to apologize, and welcome to Stangnet

longtubes make more power, and are louder/throatier sounded.

shorties don't make us much power, especially at the top end, but are quieter and do offer good gains over stock style manifolds.

Tri-Y are old designs and I would say offer gains similar to shorty/midlength headers. They're better than stock but can't take you too far.

Don't know anyone with the JBAs or Patriots, most people buy Heddman/Hooker or Tri-y, and all are good.

Mufflers... i would go to mustangexhaust.com and see if you like any of them. Mufflers have very little impact on power (dont' believe ads that imply you can gain 20 horses just by putting a muffler on... it just doesn't make sense).