On Mon, 05 Apr 2004 19:34:48 -0700, Al Gilson wrote:

approved for unleaded auto fuel. However, I don't have any paperwork
showing that it has an STC for autofuel. Any ideas on how I could
research this information? Or...is the placard all I need?

Others have already said to contact the EAA and Peterson providing the
planes information to research it.

However, at least with the EAA STC you will have an entry in the airframe
and engine logbooks where it was applied. Without those entries what you
have is a sticker somebody bought and stuck up there, worth nothing. The
EAA STC is supposed to be carried in the plane while you're using it, so
without the paperwork you can not legally burn augogas, even if you bought
the STC.