Might as well share this don't know if this has been discussed if so my apologies. Snap in buttons that came with the stick are so brittle as a result they pretty much are all broken once i removed them never again...so screw in it is.
You can use all Sanwa OBSN-30 screw
in buttons on a Madcatz TE2 previously the placement of a screw in button (nut) on the left K button would not fit it would interfere with the joystick bracket. And not a fan of bending the bracket...
However i thought i would cut the nut of the button in half so it would fit but this causes to much work. So i ordered one Seimitsu PS-14-GN screw in button, removed the nut and used it on the Sanwa one perfect fit and no more clearance issues with the joystick bracket: