How do you know when to replace the sliding buttons in the primary? I'm replacing the teflon washers, the movable bearing and the cover's bearing but i'm not sure if the buttons are bad. I'd rather not replace them unless necessary. Please let me know how to tell if they are bad. Thanks.

 

there should be shims behind them to push them out when they get worn down. i beleave you measure gap between the buttons and the towers or some just do it when it starts rattling alot more lol. imo

 

The rattling more test is difficult as i'm not sure what is normal and what isn't. I'm not sure there is rattling happening there at all now so i'm guessing they probably are ok.