Actually, Crane CorTec manufacturered the FRP panels for Renegade at least as of a year ago. Fiber-Tech Industries purchased CorTec in March, so I am assuming they still produce the product probably under Fiber-Tech's name now.
Here is their website:
http://www.fiber-tech.com/frptruck.htm
The problem you will find with building a one off is getting good pricing on your components. Since you will be buying in very low volume most mfg'ers will not sell to you and distributors will charge you much more due to the onezy towzy quantities.
I went through this exercise about a year ago and found that the difference between what I could build a one off for, what a conversion company could build it for and the big hit I was going to take in resale value, made it clear how to procede for me. The other huge factor was time, I judged that by some of the bus conversion guys which where taking 1 1/2 to 2 years to complete a conversion and that was with help.
Keep us posted, I know a few guys have checked in here and are in the process of building rigs on their own. I am hoping they check back in with their progress.
Here are some sites that may help you find some of the items you are looking for;
http://trailer-bodybuilders.com
http://www.lupers.com/
http://www.ertrailer.com/
Bill
2003 28' Show Hauler Motorhome on a 1995 FL 120
www.showhauler.com