first year of EFI. don't have to get it inspected anymore and was thinking about putting headers on it with a dual exhaust. Will I have to make changes to the EFI inorder for it to run correctly? If so what? thanks

Nope, exhaust will not change change anything with the efi. Just make sure you re-install the o2 sensor back in to the exhaust before the catalytic converter. If you buy the correct headers, they should have a spot in them to re-install the sensor.

Kurt, Would getting rid of the catalytic converter let the engine run better, plus improve gas mileage too?

Highway mileage maybe slightly

Just exhaust mods wont give you much of a gain, looks and sounds good. You will be doing it just for the sound. Reinstall that o2 for sure. Pay attention to the type of plugs and wires you use with headers, depending on your header you may need special angled plug wires and both need to be heat resistant. Or header wrap. I have a personal hatred for headers on daily drivers casue they just get in the dang way, lol.

another thought, if you are altering exhaust, when you remove the cat., or shorten the exhaust, or "free it up" you are also removing back pressure that your engine and valves need, if the truck is an 88, how many miles are on it., and the condition of the internals of the engine before improving speed....just a thought,