More power to you if you can do it in any way less than what a servicer would do. And this is it...
Unglug the unit. Remove lint screen and 2 screws there. Reach your hand around the control panel and give forward pressure while lifting the front edge of the top, releasing it from the front. Rotate the top up on its hinges. Remove kick plate. Remove door springs, remembering placement. Loosen 5/16" screws at lower left and right of front panel. Remove screws at top left and right of inside of front panel. Remove wires from door switch. Look inside to see how drum is oriented on the felt glide of the front panel. Remove front panel by lifting it off the loosened bottom screws and away from drum. Some older front panels have a long screw at the hinges that has to be removed. If the front panel doesn't come away easily, open the door, look at the hinges, and remove one of the 3 screws at each hinge. I think it is the middle one, but not sure. Removing the wrong one won't damage anything; just replace and move on. Once the the front panel is out of the way, you will have easy access to drum. Note how belt wraps around drum, through idler pulley, and around motor pulley. Draw a picture if you need to. Hold idler pulley to remove spring tension, then remove belt from motor pulley. Stand up and use belt as a holder and lift the whole drum out of the cabinet. Replace one or both rollers as needed. All the parts will come with each new roller. Clean the shaft with a solvent or rust buster if gummy. Put a touch of turbine oil on then load the roller.
To replace the drum, move the right roller foward on its shaft. Lift drum into place and turn drum by hand so that the rear seal flares outward, allowing top of drum about an inch of clearance from rear bulkhead so that there is room for the rear seal to move back into place. It will probably do this naturally. Load belt through idler and onto motor pulley. Put front panel on using above instructions in reverse, reaching inside to pull up on the drum and onto felt glide on the front panel. You can also open the door and pull drum onto the felt glide if necessary.