[DCSpecial]

With a 6" lift you'd run a 6245 front:
Bilstein 5100 - 3"-6" Front Lift Application - 1999-2004 Superduty 4wd - 5100 Series (Lifted Applications) - Truck Toyz Store

6246 rear:
Bilstein 5100 - 1"-3" Rear Lift Application - 1999-2004 Superduty 4wd - 5100 Series (Lifted Applications) - Truck Toyz Store


You'd run a 6250 rear if you had a 7" lift or taller.....but a 6250 is a 5125 shock so it's only a one year warranty. A 465 is also a 5125 shock, with less travel than the 6250 (11" vs. 14")