If you have stock manifolds you need the first one. The second one is for LT headers and will be too short and won't reach the manifolds.
Especially if you have no plans on LT headers....get the first one so you don't have to pay more $ to have it fabbed. I would say if you planned on LT get the shorty and have a exhaust shop fab some done pipes to bolt into the shorty so you can change to LT later, but since you are not going to just get the one that fits. I have stock manifolds, pro chamber, and Mac catback....sounds amazing but not too loud (I have a convertible and my kids like riding in it so I didn't want it to scream so they covered their ears, I want them to enjoy it)
2004 F150 4x4 Lariat Supercrew, 5.4l, Black/Arizona Beige (daily driver)
2002 Mustang GT Convertible, triple black, mach 1000 system (Summer Car)
2001 Ranger Edge 4x4 xcab (sold to cousin)
4.10 Gear/RPM thread