In a comment to an earlier post an anonymous, self-described "aspiring 3.0 gm" asked about conversions of old Gygax modules. Here's the conversion of Keep on the Borderlands that I used back when 3e came out:
You'll need a copy of the original module to make use of the notes at that link. As I recall the conversion worked out pretty well until I went and screwed things up by experimenting with these weird new 'template' rules. At the time I hadn't really bothered to read what an 'ECL' or 'CR' was supposed to be. The look on Rod's face when the gnoll breathed fire was almost worth nearly wrecking the campaign.