I 'flipped' the axles on my '08 Vortex TT toyhauler. I bought the kit from Etrailer, as my springs were beneath the axles. It took me about 6 hours including a lunch break to do it with my dad's help. If your rig is a 5th wheel, several on the RV.net forum have done that by making an additional sub frame and raising it that way. My buddy and I raised his TH 5er by putting in thick walled 2" square tubing under the springs and used longer and stronger U bolts to secure it. It's been that way almost 12k miles now and no problems. Although in theory, a sub frame would probably be safer.
On Edit: Yours is a 5er and will probably be tall enough to haul it with your late model truck.
2012 Sandpiper 365SAQ weighing @ 15k, Onan, 2nd air, slide toppers, TST
2013 F350 6.7L Lariat 4x4 CC DRW,Viair 1007, Ride-Rites, Edge CTS, B&W
2001 Chevy 3500CC DRW 4x4, 8.1L, 4.10 gears w/ Detroit TrueTrac
2001 Ford Excursion Limited 4x4 7.3L,V/B Spring Mod, ProComps, Hellwig Swaybar, & other 'Necessities'