Jason one of the most popular and cheapest brake upgrades is installing the Mark IV front calipers, SVO master cylinder and then perhaps rear disk brakes from a thunderbird or use the Stainless Steel Brakes rear disk brake kit (same thing). I did this with both my stangs and it works great on the street. Here's a link to an earlier post on this subject:
pub66.ezboard.com/fv8mustangs75426frm1.showMessage?topicID=210.topic
Another upgrade that has become quite popular is to swap in 5 lug front calipers, rear side axles and brakes from a later model mustang. The downside is you can no longer use your stock 4 lug wheels. The upside there is a far wider selection of 5 lug wheels available on the market, including the new Cobra 5 lug wheels. Of course, the brakes are also far superior to those found on the 87-93 fox body mustangs, even with the SVO/rear disk brake upgrade. You can check Ford Motorsport or what is now called Ford Racing for a complete kit for this upgrade.
Another option is to go to an aftermarket supplier such as Baer, Wilood or Stainless Steel Brakes for a complete brake upgrade package. These companies offer superior braking systems for your
stang. This route is probably the most expensive but the braking systems offered are also considered the best!
What option you choose should really be based on what you intend to do with your
stang. For street and limited road racing then either of the first two options would probably be adequate. If you intend to do some serious racing or just happen to like the best then check out some of the packages from Baer, Wilwood or Stainless Steel Brakes.
You can find all three websites on our Mustang Links section: Here's the link:
www.v8mustangs.com/MustangLinksParts.html
Hope this is of some help and please keep us posted as to what you decide.
Cheers,