Forgot to mention also that the hoses are pretty tight on those connection points. You could put a small hose clamp on the mstr/cyl reservoir and one on the mstr/cyl under the dash to remove any doubt. The push-in insert into the mstr/cyl is another story as it can't be clamped but if it has been on there for quite a long time, probably adhereing
As Murphy's law goes, if you don't want it off, it will, if you want it off, then it's a buggar to remove!!