Go with at least 3.73s or maybe even 4.10s like ktpman suggested. Think Lightning here. I'd bet there are underdrive pullies out there for the 5.4L. As many L owners there are that are taking off their Eaton's and putting on Kenny Belle's you could probably pick up an Eaton from a Lightning fairly cheap. Is your truck a reg cab short bed? If so get an aluminum driveshaft from a Lightning (parasitic HP loss in heavy steel shaft). As for the Gibson exhaust I haven't heard anything good about it. I would steer away from it. You can get full exhausts, headers and all, for the 5.4L. Check out
www.nloc.net/ and
www.f150online.com/ for more info. You could always go get some Nitrous Oxide, hehe.