First, use the K&N RX-4750 filter. It has a good base for mounting a heat shield, and provides a hole for the optimum IAT location in the base of the filter (or a good spot for Methanol injection
This filter will make things ALOT easier when it comes time to mount your heatshield. Now fab up a template with cardboard and tape. When you have it right, buy some clear acrylic sheet from Home Depot, and put it all together.
Reference my sig pic. Anyone still have any shots of my filter back mounting? They're around here somewhere.