I converted my SSC, SOHC neon to IT prep last year. I went with the TTI Long Tube and highly recommend it. It bolted up very easy and although I have not had it on a dyno I could really feel the diffence at top end. This along with a Iceman cold air intake really brought the car to life on top end.
I would suggest ordering it directly from TTI, I had ordered mine from a performance place online which I will not mention the name here and never got it, had to cancel and demand they issue credit on my card. I ordered it direct from TTI and had it in 2 weeks.