As a first time Fox body owner beware of cracked and failing torque arm boxs. The boxs that hold the control arms on these cars are one of the weak points and a serious issue that needs to be adressed.
For your radiator beware of japanese knock off radiators, they are terrible and a 2 row radiator wont be enough to keep your 5.0 from having cooling issues you will need at least a 3 row radiator. As for the water pump it is possible it is the wrong one and is a reverse rotational water pump, my advise would be to replace it with an electric water pump from Meziere and forget doing aftermarket pulleys. I have alot of information posted on this forum about pulleys vs electric water pumps, if you use the search feature for Meziere, you should be able to find it. Having an electric water pump is a huge power advantage. An electric fan will net you a few horsepower but there are other places to mod first.
A Mac prochamber H pipe with a Flowmaster catback is a good compliment to you BBK shortie headers. This is the exact exhuast system I used to run on my old 93 cobra and it is very cost efficent with awsome sound.
You want that cobra intake manifold installed as soon as possible as you will notice a good gain from it.
As far as cam choice goes I would leave that to a later date and focus on getting a good set of heads first. If you insist on doign a cam right away this one will net you some solid gains without you having to make any other modifications to run it as its considered a OEM replacement cam. It is actually a performance cam and will net you improved performance.
Comps magnum 266HR... COMP Cams: Magnum, 266HR <br> Good OEM Replacement, works w/ Stock Computer & Injectors
Gearing is an important upgrade to mustangs as the most effective bolt on you can get for the money. Assuming your car doesnt already have aftermarkey gears reach for the 3.73 gears if your car is manual, if its an automatic you have to go one gear set higher to acheive the same performance so 4.10 gears are your best option for automatics. A chip or tune of some sort will be required for this to keep your speedometer correct. Do not do these yourself they require profesinal instalation.
Save your money and stay away from CAI tubes unless your buying a C&L or JLT CAI.
With some good lightweight wheels and sticky tires you should have no problems getting your fox body into the 12's with the mods I listed.