Gbc dirt commander questions

I really like the dirt commanders on my 900S, but I wish they were a little taller and I wanna move up to 14" sti hd5 beadlocks. How true are the tire sizes for the dirt commander? Mine are only 25" tall with 10psi in the stock 27s.

If I move up to 29×14, will I need to put in a clutch kit and will it cause axle problems? Will they even fit a stock 900S? I mostly ride trails and only go through the mud when I have to, so I know that’ll minimize some of the problem right there. I do plan on eventually getting the 1.5" offset high clearance arms so that’ll help fitment as well