You may not need the bags inflated if it's that light. The WDH will probably handle the sag..especially with 1000lb. bars. That being said, you could probably go lighter. I had a 05 F150 5.4L and towed a 4000lb. cargor trailer and never had the need for a WDH, just sway control and the truck handled it perfectly. jm2c.
2013 Jayco Eagle 328 RLTS
2012 Ford F250 6.2L 4x4 CCSB W/Air Lift air bags
2002 Coleman Bayside Elite (traded)
Me, Momma and Charles (RIP buddy)
And introducing Sofie!! ;)