You asked for an affordable alternative, here they are!
GruvenParts.com now has affordable front brake duct brackets made specifically for your E36 BMW (including M3 and 328). These brackets are TIG welded by our aerospace machinists then powder coated with a thick layer of glossy black to protect them from the elements. Our E36 brake duct brackets have half of the air inlet blocked off to prevent cold air from being blown onto the brake rotor surface. Cooling air is routed directly into the center of the rotor and out of the rotor vanes. This method prevents abrupt cooling of the rotor surface, which causes premature cracking.
These brackets come 2 to a set and can be ordered with 2 hose clamps as well as the orange silicone SCAT tubing.
This mod does NOT require the hub to be removed. It does require removal of the inner shroud by cutting with tin snips. The inner shroud is not used after installation of these brackets.
Fits All BMW E36 (including M3 and 328)