I use the Pro-M 87mm with my Roush Cold Air kit. It works just fine for my 98 GT...
(Make sure its calibrated correctly for your computer and injectors. Your best bet is to give Pro-M a call. Read more info here: )
http://www.pro-flow.com/87mm.htm
Warning: I don't know how this will/ or will not fit with your MAC fenderwell kit.
Hope this helps...
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98 GT
Bassani X-pipe, Dyno-Max Cat backs, 3.73 gears, Steeda shifter, FMS pullies, 87mm MAF, Roush cold air kit, Eibach springs, and Zex 75 shot
[This message has been edited by Hammer (edited 05-09-2000).]