Based on the information you shared (missing GVWR and Cargo Max, as well as TW - a scale is necessary to know TW) I can pretty much guess what these are, however. Based on 1400# and a full fuel tank only, you would have a tongue weight of about 580# a TWR of 6.5% and a reserve cargo capacity for everything else you can carry (LP, water, clothes, food, et al) of 814#.
If you add 3 deep cycle battteries to the tongue (suggested by PH), it brings the TWR up to 7.7% but reduces cargo to 660#. Theoretical doable.
But, 2000# in garage, not so much. Rear axle upgrade won't increase GVWR (not offically anyway).
This is based on toy weight 52 inches from the front wall. If you kept the 188# in the fuel tank and loaded the garage to the max (2K) your TWR would be 4% and reserve cargo capacity would be 214# total.
I would guess you have the generator the extreme package and maybe the walk-thru dinette in the garage.
It is my contention that the 29HFS garage, based on TWR, should be rated for no more than 1500#; less in practicality if you want to add a battery, a small amount of water and a lawn chair or three. Your cargo would want to be as close to the front as possible, as those pounds regain some of the TW lost to garage weight.
Oh, and 2000# loaded ideally in the garage puts 2600# onto the rear axle pair, if they share equally, which experience says they don't do exactly.
XLR Hyperlite 29HFS
Ram 2500 6.7L CTD
A Modder's work is never done!