Ok so now you take your max weight and start the math. They ususlly account for a 150# driver, then you need to subtract other weights in the truck such as passengers. That weight for the trailer you looked at is estimated shipping weight, you need the actual weight. Once you add batteries, LP, supplies, camping gear and toys you'll be right up, if not over your max weight. For a short trailer that's one thing, but with a long tail heavy toy hauler that's complete other story.
nayther brings up a great issue, finding a good drop hitch and equalizer hitch. That will work with your lifted truck. I don't know if Hensely makes drops that big, but that's the type of hitch you're going to want/need.
Do what you wish, but my gut tells me that you'll be buying a bigger truck sooner then you think.