Dont know about that, pulled a F250 diseal with a huge aftermarket steel bed and aux 50 gallon take out of the mud last weekend with my M8000. Straight out. The 250 was very close to the frame. and the tires were suctioned pretty good.
Not saying a m1200 and snatch wouldnt be helpful but that seems a little excessive.
Depends on how sticky the mud.
Get something bigger if it won't break the bank. 9000or 9500. Also buget for a good recovery kit with tree strap, D-rings, and snatch block. A winch with-out that stuff us not so useful. General rule is to 1.5X weight of truck. I stalled 9000lb warn a couple times in snow before getting a snatchblock.
If you really get stuck in that much mud you're gonna need to get the t-case output seals replaced. Ask me how I know? My advice is stay out of the mud.