I've bought my glow wire by the spool in the past. I did a acrylic coffee table out of CD's for a friend, and used about 150' of wire in it. As long as you use a good inverter, and don't go for maximum light output, it can last 5000-6000 hours. With 150' in his coffee table, it glows a very bright red, and can easily be seen with the lights on, in a cab though where your only talking 10' under the t-molding, its much too weak, But around the edge of the CP is a pretty good place. I'm working on something for mine now, routing a very small channel into the acrylic CP top to fill from behind with EL.... EL acts much like neon in the respect that if you vary the input freq. and duty cycle you can get some cool effects. Ever seen neon that seems to light up from one end, then slowly illuminate over its length? I'm working on that type of effect that will "write" out the name of my cab over the CP.....
If your going to be buying a bunch of EL wire, forget the 6 foot and 10 foot kits etc... They charge a arm and a leg for the stuff. You can find it online for around $1.50 a foot, and about $5-$10 for a inverter, depending on how much you are trying to light up.
sd