98CobraConv, you got to step up to a 4.10:1 gearset. You know your 4.6 Mod motor doesn't have alot of torque, but you can rev it to at least 7000 rpms with no problems. Go with the 4.10:1 gears! If you drag race often, go with a 4.33:1 gearset.
www.jegs.com has a ring & pinion and installation kit for the 8.8" Ford rearend. Good luck!