I built some simple heat shields from SS sheet and attached via sheet metal screws to the frame back when I first built my CRL. Between the SS shield and fiberglass I put some high heat insulation material. My brake lines run behind the drivers side shield so they don't get cooked. My CRL has been on the road for 20 plus years and 40K miles and the fiberglass footboxes are still good as new
I'll try to take some pictures and post when I get a chance. Building the shields was fairly quick, easy, and materials were not expensive.