What should I be looking at to get? Since this is my wifes car I have been looking for used parts to use to upgrade it. I am not sure what size TB to be keeping my eye open for however.
Well, I don't see any mention of an intake manifold on there, so if you're upgrading from stock, I'd look into picking up a complete upper and lower manifold from a '96-early '97 Explorer from the local wrecker, to compliment your heads as a priority before the throttle body. They'll move a lot more air than the stock set up and if you're lucky enough to get one complete, you'll get the 65mm throttle body that comes with it anyway. You'll need to modify the throttle linkage a little, but it's no biggy.
If you don't get a throttle body with it, go with something in the 70-75mm range by one of the more popular brands (BBK, FRPP, Holley, etc}. The only ones I'd really avoid are the overseas brands. Their quality tends to "suck" (no pun intended) in comparison.
Anything over stock, more or less, cam lift would be hard without milling the pistons for clearance. You could put 1.7 rockers on the GT40/Exploder heads. Do the MAF install, it makes a big difference.
I found a complete Trickflow Street heat intake for 400 bucks. (is that a good deal?) Thought that would work nicely with the Holley heads. Probably just leave the factory cam for now. See if the intake and the heads works with the SD Computer