Advice needed vs 71 Duster rear wheel bearing replacement

You need to download the 1971 Plymouth factory Service Manual from here:

http://www.mymopar.com/downloads/servicemanuals/1971_Plymouth_Chassis_Service_Manual.zip

Then read section regarding rear axle service. Plenty of folks here will answer your questions once you understand the basics. Not a difficult process but it needs to be done right! Good luck.......