yea SLP is expensive but the parts are quality.. i know.. try this... i have the SLP X pipe that i can exhange the parts for(i can make it a shorty once i get LTs and i can take the cats off and make it an off road X when i want)...
You could go with SLP LTs if ur not an sn-95 cobra(96-98) ... umm yea ude want MIL eliminators with that... once u have LTs u dont need a tune but once u have a full exhuast and other mods it helps since u can retune the car and get more HP out of what u just put into it...

Ur set on the LM1s arent you? u might be disappointed... it is reaaaallly loud lol.. the LM2 which i have is more refined and sounds more muscular.. but i dunno u might like it..

you could go with BBK LTs, not the greatest but u can get um for around 400 or so.. we have a group buy going over on www.svtperformance.com for BBK LTs for 400...
other then that they become quite expensive... and make sure u get ceramic coated....

but please go check out the website i linked you to and sign up.. you will find it extremely helpful, and moreso then here.. theres a specail section for our cars and every other cobra and specail edition ford vehicles... and belive me they can give you more info and more detailed info then i ever could lol...