Well, make sure to double-check exactly what you're paying for. I'm paging through my Ford Racing/SVO catalogs and the only 80mm MAF sensor I'm seeing offered is the one that comes with the mass-air conversion kit for 93-95 351W Lightnings, M-9000-L58. There's a standalone Ford Racing 70mm MAF that's calibrated for 30# injectors and a 89-93 non-Cobra EEC (M-12579-A70) and there was a 90mm MAF that was briefly offered in 1995 for 36# injectors and a 86-93 EEC (M-12579-A90).
The 80mm MAF for the Lightning is calibrated for 30# injectors and a Lightning EEC. It might or might not fit your Mustang's housing, and it'll probably need to be recalibrated to your setup.
Edited to add:
I'm pretty leery about the fact that they claim it'll fit "94-98" Mustangs. 94-95, and 96-98 Mustangs are completely different engines and EECs. Having said all that, $65 is pretty darn cheap for a brand-new performance MAF.