Apologies for the mistake in thinking this was a rancher, I'd read a thread previous to this about a rancher!
Realistically for mudding I'd do the following...
Snorkel and jets to suit or a tuner. 2" bracket lift. Extended vent lines. Rear swing arm and shaft stretch. Minimum of 50% GR and tyres between 28 and 30 inches. (I personally would opt for a skinny tire set up, personal choice though of course)
BKT's are cheap and relatively light, very good and comparable to all the top brand choices of tires on the market.
I have 28" mega mayhem's on my foreman 450 with no GR, useless in the peanut butter mud unless I use 1st gear, even then it does struggle at times. A great tire, they do dig a little and are slightly heavier than other options out there. Tire choice is a very personal thing I think.
Check out 'mud puppy' on you tube, he did a few great tire reviews not long ago, very informative and very useful, definitely worth a search.
98 300 Fourtrax 4x4
Custom built mud bike - Now sold.
2004 Foreman 450S
Fully overhauled (nut & bolt rebuild), 2” lift kit, 28” mega mayhems, ITP delta rims, ES floorboards, 22” LED lightbar, Pyle Bluetooth sound system.