I run 26" on 12" rims with a 2" lift. No spacers necessary and no rubbing. I agree with above that the 26 or 27" will be ok on the 14" rims as long as you go with a slight lift. Gotta watch that motor mount clearance.
I put 27" ITP Mudlites on and love the tires (12" rims). They pull great in the mud and are not as rough as I thought they might be. I did put 2" spacers on each side front and rear. There was not enough clearance with the motor mount on the passenger side. Side note, last time out my wife smoked and stretched the belt because she went up a hill in hi (she stopped half way up and then went again in hi). I have since ordered the severe duty belt and will install it before I go out again. Hatfield & McCoy trails Gilbert WV 3rd weekend in Nov. Hopefully the belt will do and will not have to get a clutch kit. We'll see, hope this helps.