I get kinda preachy about weights, so I'll apologize first.
If the advertised weight of the TT is 6200# then that's "roughly" what it will weigh from the factory. That's an EMPTY weight, no batt, propane, water. We found on our 1st TT (X23B) we weighed about 1000# more than the yellow sticker after we put all our "stuff" in it. So you could estimate 7200# in trailer. The "ideal" tongue will be 13% of that, so about 936#. Add 75-100# for a WDH and you can expect the tongue weight will be 1036# (I try to estimate on the high side).
Next, load up the tribe, fuel up your truck and head for the CAT Scale (the CAT Scale is your friend). For about $10 it will tell you what the front and rear axles weigh. The difference between the drive (rear) axle weight and the Rear GAWR is how much additional weight you can add to the rear. If that's more than the 1036# (say 1500#) then you are good to go.
This a link to a sticky that will help you understand the Weighing process
Good luck and keep checking in.
2013 F-350 CC SB 2WD 6.7PS
2013 Eagle Premier 351 RLTS
-SOLD- 2012 X23B
-SOLD- 2003 Ford Expedition 5.4, Bilstein shocks