Looking at your AF 1150 and all your extras, I would not stray too far off into the sand. The problem here is weight and dually’s. Heavy dually’s typically don’t do well in deep sand or any sand for that matter. It takes a long time to deflate six tires down to a usable pressure for sand. The pressure for duals is 5 or so pounds higher than for a single rear wheel. If you really want to get well off into the sand, be sure to have a great way to re inflate the tires. dually’s typically are narrow on a narrow rim without much sidewall for deflating. Purchase the best, most expensive 100% duty cycle 12volt high volume portable air compressor made for big rigs. Take 2 or 3 high quality tire pressure gauges (they are notoriously inaccurate) and the final thing is to take a friend with a similar weight TC along with you that has a lot of vehicle recovery experience; and a 20K tow strap (no chain) and D rings to attach to whatever recovery attachment points you have.You really need secure hooks or points for recovery. A lighter weight ‘friend’ will not do.
I’ve owned 13, 4WD’s over time; half of them with a winch; many with full locking diffs; wide rims for deflating, over sized tires, big clearance and used my winches hundreds of times for extractions. I took that experience and applied it to a TC which weighs twice as much as all my Jeeps, Scouts, and Land Cruisers.
Some who insist on taking a dually on sand will put a 1/2″ spacer between the rear wheels to allow the duals to run at a lower pressure. It takes a while to heat up duals, even when they are touching.
Finally, if you insist, go out and make your own mistakes and worry through a way out of them….with that same sized friend’s rig with a winch and sand travel moxey. This was my 1st 4WD campmobile in 1967. 1949 Willys Utility Wagon with a Chevy V-8 and my first springs over axle attempt. The 2nd is my 1982 CJ-8.
2020 Ford F-350 XLT FX4 4WD SRW SB SC 7.3L Godzilla Gas TorqShift 10R140 397 amps dual Alt dual batts Frnt Dana 60; Rr Dana M275 E-locker 4.30's 4580/4320/4066# payload 7243# curb wt. 11,300# GVWR 5-er prepped. 2020 Northstar Laredo SC, 12v compressor fridge, cassette, 320w Solar sub zero insulation.