US bumper lightening mod, who has the link?

[tomc at satx.rr.com (Tom C)]

I've done this to my rear bumper and am about to start on the front, it's a
lot of work but pretty straight forward. Keep your drill bit lubed, there's
a lot of spot welds and you'll go through quite a few bits if you don't.

http://www.myscirocco.org/_MARS__81S/Lightened_Bumpers/lightened_bumpers.htm
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