I finally found a site with the info I was looking for:
http://www.enworld.org/forum/conversions/245278-attempt-rebuild-conversion- library-please-upload-conversions-3-5-here.html
and
http://www.enworld.org/forum/conversions/111444-notes-my-return-tomb-horror s-conversion.html
and
http://community.wizards.com/go/thread/view/75882/19871670/Converting_RETUR N_to_the_tomb_of_horrors.?pg=2
If anyone is still looking for this info (I realized this was an old thread after I posted) there you go :)
Blessings & Peace,
Hugo