[ZL1power69]

welcome to af. i will give you some ideas as to what you can do but please look over the other threads in this section as they are performance oriented. also look at "real performance from a vortec v6" and "v8 performance from a v6".
- first, the k&n kit is a nice piece that comes with a heat shield but you would be spending more money than you need to. Ebay has intakes for about $20-$30 that perform exactly the same. they dont come with a heat shield but thats cheap to make.
- TB spacers do absolutely nothing for the 96 and up 4.3's. dont waste your money. a larger TB could make a difference (honestly ive never seen any aftermarket TB for the v6). if you want to keep the stock TB do the throttle plate mod which involves cutting of the half moon shaped deflector of the TB plate. that will improve your airflow a bit and is free to do.
- of course, a high flow exhaust will help your performance. a cat back is not really nessesary to get decent gains. a universal high flow muffler will do the same thing. headers are also not really nessesary unless you are going to use forced induction.
- i think the programmer you are refering to is a hypertech Power programmer 3. your friend should be able to plug it back into his truck, restore the stock settings, and clear the unit of all data. the performance tune may help a bit but i believe you have to use 93 octane fuel with the tune.
- as for the fan, the flex-a-lite unit is over priced. an electric fan from a 96 3.8 ford taurus will move as much, if not more air than aftermarket ones and can be found in locall junkyards or online for cheap.
any other specific questions, just let us know and we'll try to help.