I have began to restore rebuild a out frount deck gravley pro master 50 rider. It has a 16hp. koler cast iorn horizinal engine. A 2 speed axle, 2 speed trans, and aforward and reverse lever. I need to know about tire size for the drive axle and the frount casters. also any other info that could be helpfull. (like model or ser# location. ) the rear steering wheel size is 6.50x16x8 it apears to be the right size. this is my first gravley that belongs to me. any help will be apreceated.