Dennis Taylor came by our shop and made the foam insert with the ISP kit. It really does fill in the voids that you wouldn't think would be there, even if the driver is a tight fit in the car. I would try to have someone do this who has done it before or you may be buying a couple of kits. We are quite happy with how it is turning out. Dennis makes house calls so call him if you need one. Here are a couple of pictures of the insert in process.