I just ran across this video that shows how to adjust Cubase's meter bar colors to assist with gain staging. From the quick check I just made, it seems that SONAR does not offer this level of customization. Is it possible with the stock meters?
 

I can recommend Mr. Anderton´s article:
: The Overachieving Meters.
It´s the first article of Craig Anderton´s 
Fridays tip of the week
http://forum.cakewalk.com/FindPost/3074657
 

Go to Preferences > Customization > Colors and type VU into the search box. You can customize both the high and low level colors. This blog post shows one example of customized meter colors. You can't change the levels at which the colors change, but in the post Pragi references, it describes how to set the meter resolution, which I find tremendously helpful (as well as how to show peak and RMS values at the same time).
 
(Pragi, thanks for pointing out that tip! Note that I changed the URL in your post because the name of the URL for Friday's tip of the week changes every time I post a new tip. Instead, I posted a link to the tip you referenced. You can find a post's "perma-link" by clicking on the post number in the post's lower right corner.)

Thanks! I'll give these a go.