Ok, if you're worried *for* the crt, as opposed to *by* it, that's a different thing.

However, it takes a lot to injure the crt, so there's still no big reason to worry [unless you're planning to operate on the innards with a hammer, that is].

The only somewhat vulnerable part of the crt is the piece at the very end. But as long as you watch out for it, you won't have a problem. To break it requires more than a casual act -- the typical way to snap off the end is to be impatient when trying to install/remove something else, and accidentally strike the end with a fair amount of force. For installing ram, you won't be using any substantial force at all. Just exercise ordinary care, don't rush things, and you won't have a problem. You shouldn't feel inhibited at all about upgrading ram. It really is a simple and safe (for both you and the mac) procedure.