From YetiFan.com :
Yeti original prototype ultimate frame. Frank the welder and Chris Herting and Myself worked on this project in Agoura Hills California in the late 80's. FTW was very fond of this bike and gave it a rather wild spray can paint job. Made of 4130 Chromo
I am quite sure the original MBA article on this frame/project has been scanned and posted on MTBR VRC about 5 years ago.
For advise and exposure I would indeed consider sites like:
yetifan.com
retrobike.co.uk
mtbr vrc
mtb-news.de classic