I have an 05 Kodiak 450 and I had the oil changed by the dealer originally, but now it is time to change again, but I can't get the socket on the drain plug. Do I have to remove the plow hook up and skid plate? Any help would be appreciated

 

You can drain the oil thru either of the two drain holes in the bottom of the engine. Im assuming the one under the dipstick area, is the one thats blocked. If so, theres a much larger plug in the center of the engine case. Careful when unscrewing it...theres a strong spring underneath it.
If you go to the ronnies part finder, look in the oil pump diagram, and its number 15.
ronnies