The factory 8" subs mount to the iinside door panel which has a built in enclosure. I would be surprised if Ford manufactured different doors depending on what stereo was in the car. You should not have to cut the metal in the door to mount speakers, but you will need to modify the door panel.
2010 GT Premium, Saleen Series VI.5 w/3.6 pulley, Dynotech DS, Pypes LT, O/R H-pipe, High Flow Cats, Magnaflow Street Axlebacks, Steeda Sports, Koni STR.T, BMR Adj. Panhard, UCA & LCA, Stoptech Stage 2 Slotted Brake Kit, Autometer Boost & A/F gauges, JLT Series 3 CAI, Kenne Bell BAP, CHE K-member Brace, Steeda Battery Relocation Kit, & other supporting mods.