Anyone know how to replace the rear-quarter turn signal marker lens (reflective red plastic cover at right rear) on a Z4?

I just bought a 2004 3.0, there are a few nicks here and there which I'd prefer to fix myself, and the biggest problem is this cracked lens. Seems like it should be fairly easy to pop out and replace, and by doing stuff like this, I'll be able to afford to do some other things that would require full-price dealer labor (like having an alarm installed--why do Z4's not come with alarms?!). But how do I do it? Will I have to take the rear bumper off?