Dude.... screw that... DIY.... do like they do on fishing boats. Get a block of zinc and ground it on your car's body. It'll do the exact same thing. It creates a galvanic effect and so the zinc block will rust first. You just need to make sure that the ground to the zinc block is good by cleaning it once in a while. What I did is I have the block in a small plastic box in the trunk with a large 4 GA ground wire running through the plastic box to the car's chassis. This will keep all the zinc oxide dust contained in the box so it doesn't go all over your trunk.