You never said which model machine you have? Some drums split in the center while others the front plate comes off and on the older models you had to remove the back panel. Some machines come with welded outer drums which mean you can’t change the bearings at all. So before you can get anything like an answer you need to say what model you have. Although there are tools to assist with bearing changes it can be done with just a hammer and a cold chisel, but you need to be careful you only hit the outer ring of the new bearings when fitting them.
casper......www.selfix-uk.co.uk, March 2010