I don't own a Ford six, however I own a nissan six and face many simular problems...
here is a starter list (not in order) for you to look into:
-headers (good type)
-Cam (oh man everyone has cams for fords!!)
-Intake (cold air, tickford box etc etc)
-XR6 or chipped computer(higher rev limit for cam, no speed limiter better mapping)
-MAKE it a manuel (auto limited top speed for reason)
-Low LSD diff (~3.45-3.7)
-Some fat low pro rubber/wheels
-Brake upgrade (pads, discs, calipers, fluid)
-Suspension (lower it 35mm)
-Removal of excess weight (spare, jack, some underbody/noise insulation, alloy crank pully)
-Body kit stuff
-Interior bits like chrome doorhandles, chrome ghia bits, leathery bits etc
My general prefence would be to pursue say a XR6 (or simular) cam, computer (xr6 or simular), Headers and a 3" exaust. If you want to go all out on a wild cam I would suggest you go on a lower something like 3.45+ diff at the same time.
However pick your cam carefully, some can be crappy, and its a expensive thing to have a crappy selection on.
I would do in order:
-Intake (cheap and quick and worthwhile)
-Extractors+Exaust (most benificial over all maybe)
-Cam and computer (pushing the last little bit and spend your time making desicion)