OOOOOOOOOOoooooooooo!!!!! Dont know more than me jobs worth init luv! lol
easy, left side,take the magneto cover off, take the sproket off, gear seletor off, losen clutch cable as youll be taking that off too.
right side, (for wet clutch) drain oil and water, disconect the hose's from water pump, remove the engine cover be careful there is a washer on the water pump that drops off, youll see the clutch and various other bits, (this site says look for 2 white marks on the primary and secondard gears and line them up i couldnt find any and when i asked noone answered, make yer own so that when you put it back together it all lines up) remove clutch bolts and springs remove clutch plates (dont mix em up) get yer impact gun stuff a rag in the basket and get the clutch nut off, remove cluch assembliy, remove kickstart shaft (it slides out) remove the water/oil pump drive gear (on a triangle bracket 3 allen bolts top right of gear box case) watch out for the 2 LITLLE O RINGS AND 2 DOWLS on this part renew the o rings, youll now see a small plate at the bottom of the transmission, remove the 3 bolts for this, and the remove the bolts holding in the transmission plate, it wont come out in your hand but a gentle tap on the sproket shaft will move it, and then give you enough to grab, take it out slowly, and thats it, a bit basic but if there is any bit you need more info on let me know, I havent put my gearbox back yet BUT matt said make sure the gear return spring is hooked up as you slide the transmission back, (looking at this i think he means as the gear box goes back in lift the spring so that it sits inside the case and dosent get caught as you push it back) he also said use plenty of grease so as not to catch the splines on the seals sproket side. remeber to get yer torque settings.