It's a pretty tough job. It sits ontop of the fuel pump I think and in order to get to it you pretty much have to tear down the front part of the engine. I had it done by a mechanic and it cost a little over $500.
I'm pretty sure the DIY section of the forum has a write up on replacing the FPR. You don't have to tear down the engine, just the periperals on the front so that you can get to it.
If your FPR is bad, you will usually throw codes. I would try to diagnose it a little better before I tried to replace a part that is that expensive.
Also, you may want to try changing your fuel filter again. They are only good for between 4,000 and 6,000 miles and you could have bought some bad fuel.
Clean the air filter and MAF sensor first too. When cleaning the MAF sensor, be careful with it. It is delicate. Use only MAF sensor cleaner available at most parts stores. Let it air dry naturally before reinstalling.
ok thanks guys! and now that i think about it the guy who had the truck before me did have a wore out kandn filter that looked like he dipped it in some atf lol ill change the fuel filters and clean the MAF or as the kid up the street told me to change the plugs and wires mite help? yea sure mr A.C.E CERTIFIED mechanic hahaha