[Merv and Sharon]

Sound insulation is a personal choice. It depends how quiet you want the car to be, given it has an open roof anyway and a nice exhaust note.

Some cars are hotter than others. The Harrison for example, seems quite cool, even with minimal insulation. As 400TT said in another thread, heat insulation is the priority for most, and they use an aluminised cloth with woven fibreglass in between the layers. It is approximately 2-3mm thick. It will also protect the body fibreglass and paint from heat damage. Use a hi-temp silicone to glue the cloth to the body, tunnel and engine area, where suitable.

I probably over did the heat insulation on the tunnel, engine area and even around the inside of the body shell where the radiator sits and where the mufflers are placed. I also used aluminium panels in the back of the engine bay area, but that is more for appearance than functionality, I suspect.