In Reply to: anyone here have the plastic airdam from La Jolla posted by carl on March 08, 2000 at 11:35:31:
A good way to mount an air dam is to use a special threaded insert called a "rivetnut". It's very similar to a rivet. The only difference is that the inside of it has thread. To install it, you drill a hole, insert the rivetnut with a special tool (looks like a standard rivet gun, but isn't) and swage it into place. Very clean professional look.
What I do is after drilling the hole is to coat the edges of the hole with POR-15 or Corrodes and followup with a tiny dab of RTV or silicone sealant to keep rusting down to a minimum.
Also, use stainless flat washers and fasteners to install the dam. Buttonheads look really nice. In my old '76, I filled in the fastener hexes with epoxy to avoid some enterprising SOB from easily removing the fasteners (if they want it, they're going to have to work for it is my motto).
If you're in No Cal, you can buy the inserts and tool at Orchard Supply Hardware.