Camper Renovation and Capabilities of a 2007 Tundra Double

You have the truck so drop be a set of CAT scales and get the trucks separate front and rear axles weights. I don't know the Tundras rear axle load numbers but maybe in the 4200 RAWR range....and its rear axle may weigh in the 2500-2600 lb range which leaves the truck with around 1600 lbs in the bed before exceeding a tire/wheel or rear spring pack capacity number.
Weighing before and after tells the tale. Then is the time to think about any rear suspension mods if needed.....or if the camper needs to shed any weight.