how low can i go and still tow a gooseneck camper?

Camper is a 85 jayco 35 ft, probably 9-10k. Had it on the truck and measured from ground to bottom of fender and removed it and measured again....with the camper on there it was 2 inches lower. Any suggestions would be great. Was not wanting anything drastic, maybe a 3-5 drop.

just lower it and put helper bags in the rear to help when you tow