30 mm clutch vs 33 mm clutch

The center seals on my 03 Mountain Cat 900 started leaking, I found a crank on ebay for $300 and after I got it put in I found out the crank from ebay has a 30 mm shaft. My old crank had a 33 mm shaft. My question is, can I just put a 30 mm primary on and go? The 33 mm shaft has a lot longer mating surface for the primary, I was wondering if this was to accommodate the extra torque from the 900 vs the 800 that the 30 mm crank came from.

30 mm clutch vs 33 mm clutch