I have L/T's on my 97 GT 5spd and they were a pain to install but it was worth it. I picked up 17 rwhp with my headers, Hi-flow X pipe and catback on a stock motor. It may not sound like much but as the mods grow so will the HP.
97 GT 5spd
FRPP 03 GT PI heads & intake,BBK ceramic L/T,BBK Hi-flow X pipe, Magnaflow Magnapacks catback,CAI w/ 9" K&N,Accufab plenum & 75mm T/B,Steeda U/D pulleys,SCT X-cal tuner, Fluidyne Radiator,Tremec TKO
tranny, Pro5.0 shifter, Ram Powergrip clutch, FRPP Aluminum driveshaft,FRPP 3.73 gears & Cobra 31 spline diff, Moser 31 spline axles, TA girdle,UPR adjustable upper & lower control arms,03 Cobra 17X9 & 17x10.5 rims,Nitto nt555 255/40 & 285/40 tires,Kenny Brown subframes, Corbeau CR1 seats