i was doing some work on the rear rotor and i noticed the bump stop on the rear right side fell off. it's a big piece of light rubber and it is imprisoned by the spring and the rear spring pan. should i make every effort to replace this right away, or can i leave it for a while? i'm just finishing off some brake work, but it seems like a huge hassle to take apart the rear suspension to put this thing back on. it still provides some cushioning as it's between the upper seat of the bump stop and the bottom of the spring pan.

i've tried to weasel it back in, but the spring and associated components are hard to work around, and the fastener is difficult to finagle into place.

can i just leave it? (hopefully) or should i take care of this? (effort) i'm not lazy, just pragmatic.