If you get the 3500 with the auto-pop rear suspension, it is likely that the the rear will not lower further than the stock unloaded ride height. It only levels it out by adding pressure when a load is added. See the note below from the owner's manual.........
Sounds like you have ordered a truck that will work for you! I was thinking about the 3.73 versus 4.10 discussion today while doing some mountain driving.
I wish mine had 4.10 gears....especilly with the 35" tires. If I was buying another one today, it would have 4.10s. After driving mine for nearly 13,000 miles, I wish it had them instead of 3.73s. I believe the 4.10s would reduce the hunting issue mine had on hills when new.......
......I think you will really like that power train! Can't wait to see some pictures!
.......The truck does sit lower in the rear than standard 3500s though, ....
The difference between 3500 and 2500 with load height appears to be that the 3500 uses air on top of a leaf spring setup, and there isn't much compression unloaded, so the truck can't really drop. Whereas the 2500 with air is pure air in the back, so many more options for what it can do. Still don't see any HD key fob remotes with the lower function mentioned in the manual, but I did see it on the 1500 with 4- corner air.