I would probly research it on TurboFord or SVOCA to see if they got a whole system somewhere to buy all at once if not heres a thought:
Sacraminto Mustang sells a 3" DP for 109.00 and you can get a 3" Catco cat off Ebay for 45.00 shipped. The muffler is your choice but I would try Ebay or Jegs before I got one from a muffler shop. After that a Muffler shop should be able to do the rest. Now if you go dual ( in the intrest of peace lol) most muffler shops sells a "Y" pipe. If your SVO is a older 85 and under you may need to relocate the fuel pump/filter on the frame rail.
Definately look into the "stinger exhaust system".
I uses an aluminized steel 3" madrel bent pipe and has downpipes and Y's (i think)
He made mine, which consist of the 3" DP, a 3" connecting pipe to run the length of the car and stay on the pass side. I welded a "stock replacment" 3" cat from a powerstroke/cummins (anything deisel). I used a 15" borla Sportsman round track muffler and a MAC 2 peice 3" mandrel bent tail pipe.
Honestly I think it sounds great and I'm used to hearing my 351w with nothing but long tubes.
Not really loud, has a good low rumble and the turbo spools really quick.