Here is my $0.02
While I do know it is physically possible to make the returnless fuel setup work w/ a S/C, given the current availability of people doing custom dyno-tuning on contours, it will be much more difficult to get it done (even with the Mustang and its large aftermarket community, had a lot of trouble getting stuff to work when the 99 came out with returnless, it took nearly a year for Vortech to get something that really worked)
So check your fuel system, and know what you are getting into (unfortunately, I don't remember the really easy way to tell off the top of my head, but I'm sure someone will chime in with it)
Some other things to think about
1. Intercooler. if you can figure out a way to get one in there as you are putting in the S/C, you will be way ahead of the game, as the vortech setup is in dire need of an intercooler (ask anyone running the vortech about the heatsoak! WorldTour is even experimenting with a temporary water/alcohol injection system until he can make an IC fit)
2. Exhaust. Personally, I would suggest a custom, true dual exhaust over the borla and a y-pipe. A true dual exhaust, done properly, should yield better gains, including low-end torque (ask Terry Haines about this) There are other factors though that would affect this decision, like if there is a good custom exhaust shop, or if emissions laws won't let you alter stuff etc.
2a. Headers. If you can do them, go for it. I would call MSDS and ask them about fitment of the S/C spec headers in an SVT. Heck they make them, who would know better, right? (ok, ok, I would trust bnoon's opinion on something like this :D)
3. Quiafe. If you got the money, by all means, but though it is quite desirable to have one, it is not a 100% necessity like some will tell you. Another thing to consider, is that Torsen may or may not be selling their unit (which I would much prefer over the quiafe) by the time you start buying parts, so don't forget about it.
4. Additional Engine work. If you are going to be pulling things apart, now might not be a bad time to consider additional work, ie p&p heads, 3L valves in the SVT heads, etc. etc. It all depends on your timing and budget, and availability of a good shop. Also, now might be the time to think about solutions to combat non-S/C specific issues with the duratech (ie engine oiling, a baffled oil pan, and an accu-sump type oil reservior would provide some peice of mind)
When you go to actually do the work, and as you get parts, etc. be sure to use those "in the know" on this board. Terry Haines is the man to go to for anything like this, his credentials are about as good as you could hope for in this group, and he is a great guy to boot. Worldtour is a good source as well, he has the vortech on his car, and is more than likely making more power out of it currently than pretty much anyone else. bnoon is also a good contact, though he had other problems with his motor that necessitated removing the vortech from his car (poor Silvie :D)
I have assisted Worldtour in a few "troubleshooting" sessions w/ his car, and I do have a degree in mechanical engineering, and I currently work in the auto industry (my ties there kinda make me wonder what happened to your Mustang
![laugh laugh](/ubbthreads/images/graemlins/default/laugh.gif)
hope all was ok with it) I would be more than happy to help you as well. All that said, Terry Haines and his company are probably going to be the best help you will ever get for a Contour of any sort.