Unless it is calbtd. for your ecu (not the same as fox mass air cars BTW) the fox elec. will not work (or should not), it may run but not very well. The meters have a air flow & voltage table so the computer knows how much air goes into it at a cert. voltage. If there is more air, due to a larger meter, the voltage will be off. Unless its some kind of cal. meter like Pro-M, or you have some way to tune the ecu, Tweecer,Eec Tuner,PMS, ect. you will have issues outside of the fact the meter is too large.
Funny thing is that pushrod 5.0 motors dont use as large a meter as the 4.6 that are friggn' huge.