After some reading it seems that you have a 2v.
I dont know about the 5.4 but the 4.6 2v was available until 2011 when the crown vic, grand marquis and town car were discontinued. As far as the 4.6 2v anyway it had a pretty long run. Im not as familiar with the v10 but I think the 2v was available after 05 in the f series and excursion if not more models.
07 Gt Tungsten Grey
Roush (Airaid) Cai, GT500 Tb with BlowByRacing Adaptor Plate, UPR O/r X Pipe, M80's, Pypes Muffler Delete Axle Back, Sr Performance Adjustable Motor Mounts and Steeda Tri Ax Short Throw Shifter
02 Gt Mineral Grey
Steeda Sport Springs, 3.73s, Pro5.0 Short Shifter, Pypes O/r X Pipe, full 2.5 inch exhaust with M80's, 75mm Tb and C&L Plenum
87 Mercury Grand Marquis