8&3/4 gears installation kit advice needed

The pinion bearings are the same no matter which ratio gears you install in a 741 case.. They are based on the case "741" that gives you a 1 3/8" pinion diameter. The Bearing notes above are indicating which type of carrier you are using. If carrier is already setup and carrier bearings are good, they do not need replaced again to swap ring and pinion. Just buy pinion bearings, races, and pinion seal.