Chevrolet & GMC, Short Piston Rod

Place suitable gauge (J-22647) over piston rod in a position which will allow gauge to be slipped to left or right wihtout contacting studs. Center section of gauge has two levels. Piston rod should always contact longer section (lower level), and never contact shorter section (higher level). Any variation beyond these two limits would require replacement of production piston rod or adjustment of service piston rod.