First I tried to replace only the blown diaphragm in my V50 rocker cover (and ordered the diaph separately, from elsewhere) but that was a waste of time and the money - it is very, very likely that the plastic "breather cap" parts/legs (holding it in place) will snap off when trying to remove the cap. Cannot access the diaph from bottom side either.
This complete cover is a quality part and requires very little prying to get the old part out and new part in.