If you don't want to go through the trial and error of getting parts to fit, check out Ebay, the Densecharger kit is everything you'll need, it includes ABS plastic pieces that will fit your maf a gasketed plate to cover the hole from the stock air box and a K&N cone filter to go in the fender well. I had to open up the holes a little to match the bolt pattern but it was real minor. A little pricey but all design work is done for you and with my schedule it's like trying to find time to do mods is at a premium and it was easier to go this route. I'm sure there's a performance gain just not very noticable without a dyno, sounds good though.
98 4.6 SOHC, J-Modded, B & M 24K Tranny Cooler, Cold Air Intake, 76 MM MAF, RM Tube, March 1150 U/D Pullies, Poly Bushings, Air Bags, MK VIII Brakes and Wheels, Trak-Lok w/ 3.55's MK VIII Flex plate and Marauder T/C. Now that it can go, it'll be time for show.