Dually Conversion

I have a 2011 Chevy 3500HD diesel, crew cab, long box, single rear wheel (SRW), 18,500 towing capabilities. I have seen conversion kits to convert my SRW to a dually, has anyone done this this? If so, are you happen with the results? Reasons for my thinking is, I like my truck, its paid for, I bought it new and have had it serviced when necessary and it runs great. I bought a 41 ft Heartland Big Horn 3750FL, 16K gvwr and I'm pushing the load capabilities for the SRW tires. I don't need to increase the load capabilities of the truck but I want to feel a little more secure with the camper load distribution on four dually tires vs. two. Any problems with this thinking?
Also, how can one weight the truck and camper to determine the pin weight? Thanks for your positive input and comments.