Tom:
Urethane was my choice. From everything I have read, nothing else is close as far as durability. Epoxy primer direct to metal and urethane over the top in either single stage (if a straight color) or base coat with clear coat (for straight color or metallic).
If you plan to spray yourself, make sure you have proper respirator protection. Most folks recommend positive pressure systems that pump air into the mask. Air Advantage, SAS and others manufacture these systems.
Search the forums at these boards as well if you would like further research:
autobodystore.com
hotrodders.com
Regards,
Steve Lorio
New Orleans.
