AMC Model 20 rear axle:
12 bolts in smooth rear cover (no fill check plug in factory cover. fill check /plug on front left side of cast iron housing above pinion gear
AMC Model 15 rear axle:
10 bolts in cover and fill/check plug in cover.
WSC Motorsports has a rear disc brake conversion kit available for the Model 20 Rear end. Click here for more information.