It will work
Dont call ZEx they will tell you it wont work.
Ive seen alot of late model mustangs inclunding my own with zex kits.
Simply follow the directions on the kit including the throttle body wire (I think its the white wire on your sensor plug).
Yes, let the spray go through the mass air. Do not point the spray nozzle directly at the mass air unit ,it will freeze the unit wires,Let the spray be pulled through the mass air.
You can mount the zex box on the wheel side of the fender well or next to the mass air unit (engine side) ,if you have cold air;Its to tight with the stock intake tube. I used only the top 2 screws to mount the zex box next to the mass air on the fender well.You may want to rotate the mass air so the "plug in" dosent rub on the zex box.
You can mount the spray nozzle on the End of the filter(drill a hole) so that it sprays sideways or drill a hole in a cold air tube ,by the fender well, so that it makes a turn before it hits the mass air unit.
Zex will tell you it wont work,but Powerhouse performance in Oklahoma city makes a living putting zex kits in mustangs.
It took my car from 14s to low 13s.
I'm running a wet kit now but the zex was much safer.