To get to the rear pto shaft bearing, it is tougher, and best to remove the rear fender pan. The front upper is like coldone said, plus remove the plastic tunnel cover off. When my pto shaft bearing went out, I didn't have time to mess with it, and being the belts were old, I simply cut them off. New were pretty cheap, 1/2 x 22" . BUT, don't cut them as you may have a mid shaft lower bearing out. Loosen the belt adjusters till you can slip the belts off & tie them up out of the way. You have to remove the lower shaft coupler cotter pin, slide the coupler back, then remove belt from lower shaft, then tie them up high. Put the coupler back into place with pin, then start her. If the sound is gone, then must have be the upper pto shaft with bearing issues. If growling is still there, then likely the carrier bearing on hydro input shaft.