We usually use thin lexan, with some thin aluminum angle as reinforcement as needed (Under rio & battery) This year we are using Alumalite, which is 2 thin sheets of aluminum with a plastic core. The Rio is insulated by using nylon bolts and thin lexan spacer. We chose to use Alumalite to try to lessen the chance of static taking out more Jags.
http://www.harborsales.net/tabid/130... alite#Product