Always start with the simple (cheap) stuff:
The cheap stuff:
1. Do a tuneup. Replace wires, cap, and rotor. Buy a set of Autolite 3923 spark plugs.
2. Run a can of seafoam through the throttle body with the engine running hot, and a can through the gas tank. Look for instructions on the site on how to do this. Clean IAC plunger in the rear.
3. Replace stock intake assembly with any of the aftermarket ones. (There are tons of them: on ebay, through various online dealers. Take your pick. Some are cheaper than others.) You can even build your own using PVC.
4. Replace the stock 195* tstat with a 180*. Should cost 5$ if you have the tools and extensions to get it out.
The moderately expensive stuff.
5. Grab a Fastman throttle body directly from "the fastman" or get a V8 throttle body sold here. Check the sellers forum. Should be around 50$. Fastman TB's are around $200-250.
6. Harland Sharp 1.7 Roller Rockers. Straight bolt-on. Should not requier fancy tools or knowledge. Just bolt them in. HS sells them directly for 260$. This causes no loss of low-end torque and noticeably increases power after 3000rpms. part is #S70047 (You might want to have someone knowledgeable within reach should you install, so they can guide you through it or inspect the work after its done)
7. Superchips 3815. Another big improvement overall. Should be around 350$ or so. Simplest mod to do. You can also grab a part # 3715 if you want to go cheaper, but the newer one allows online updates. Don't overpay for this.
8. Replace the stock cooling fan with a black magic 150 electric fan. I did this to mine and never had any cooling issues. Might not recommend for you if you have the combination shroud (the one that includes the winshield and radiator resevoirs as they can be a pain to replace/re-route) The black magic should be anywhere from 200-300 bucks.
The harder stuff (more expensive)
9. Port the intake runners on the manifold or buy a ported intake manifold from Hughes. ( check here
) The manifolds they port are VERY well tuned to our stock engines. I used to have one and was very happy with their performance. about 400$ and you will need to send in your stock one. If you've never done this before I recommend you get some assistance with installing it.
10. Grab a set of gears for your differential. Determine your differential type (Should be 8.25 or 9.25) and what gear you have already (Im thinking 3.55). Buy a ring/pinion gear two steps up. (Example: you have a 3.55, the next step up is a 3.92. You skip over and get a 4.10)
This mod can get expensive and requires professional install. However, it is probably one of the biggest improvements you can make. It may cause some loss if fuel economy. We can point you in the right direction if you're interested in hearing more.
I wont touch heads/cam/converter/internals as I don't think you are interested in going that far.