Illustrator :: How To Know The Exact Letter Height

I am currently using CS2 working in a sign shop designing signs, banners and vehicle lettering.
 
When working with text I need to know the exact letter height, not the em and without the leading. I need it exactly the way it would measure if converting the text to outlines. The reason I need this information is that when I output the lettering to a cutter/plotter to cut vinyl media I need to know the exact measurement so I can nest my lettering on my media size. The media is typically 24" wide which gives me 22.5" of available space once the pinch rollers on the machine are considered. Pinch rollers are rollers that engage a knurled driving wheel and "pinches" the media between them and thus guides the media through the plotter. Of course, when using any media one must make the best use of it to avoid making scrap or using more than is needed for the job at hand. Converting text to outlines gives me that measurement.
 
One time awhile back I did a google search on this and found a one or two button fix that made the bounding box snap to the exact "ruler" height of the text. It worked great. But I got away from design work for a short period. When I returned I'd forgotten the process. Back when I did find it I never bookmarked or made a text file explaining the process and I'm ost in finding it again.
 
I don't know exactly how I worded the google search but the answer I was looking for came up on the first page. That's probably why I didn't feel the need to bookmark it or write it down. Now, I've googled dozens of different wordings for my question and get nothing. It's likely a nomenclature/jargon issue and I've yet to stumble on it again.
 
As it is, when I get to the point that I need to know the exact ruler height of my lettering I convert my text to outlines. But then, as sometimes happens, I'll desire to change the font or try someting different but the text is not live so I'll have to start over with that line of lettering.