Scott Bright raced Tecate last Fall on an apparently stock EC300 with what he reports was a Sachs/Zokes combo...
http://www.racermec.org/index.php?op...1037&Itemid=86
Geoff of MotoCity, who transfered the bike to him remembers it as a Sachs/Sachs combo.
Anyway, I e-mailed Les to ask him his opinion and I mentioned this thread (but he doesn't like to post much).