I've done it, it's not that hard.
Check out this link: Mirror replacement
The following link also has alot of other DIY's DIY
<img src='http://www.geocities.com/royb9t8/MY_BMW_2.jpg' border='0' alt='user posted image' />
<span style='color:blue'>My ass may be dumb, but I ain't no dumb ass!</span>