My 1998 big bear has been causing issues lately so I finally broke down and took it to my mechanic. Turns out the carb was leaking gas into the engine and mixing gas with the motor oil. The gas in the oil rotted the driveshaft seal on the rear behind the boot, causing the oil/gas mixture to leak out everywhere. He quoted me $300 in labor and $51 in parts to change the rear seal. Is this something I could do myself? I know I will have to remove the rear arm, but is this a difficult task? I consider myself very mechanically inclined.