[Stefano]

ssl78,
The Douglass Yenko was for sale in Spring Grove at the Gas/Service station which you mention. This was early 1980s however, not 1990s.
The Station was torn down and a mini-strip mall is now in its place. The owner of the station, described a bigger than average guy 6'2" and about 275 lbs was purported to be the original owner of the Camaro(still seeking this individual).
He also may have been a mechanic at Biggers Chevrolet prior to opening his own Gas/Service Station.
The Camaro only shows evidence of one repaint. Sublet and others who looked at it back then believed it to be mostly original paint.
It did have a full factory chambered exhaust system and all original components at that time including a factory Blue dot Multiplex Stereo ,as well as the options you mention.
Some remember it with a Rosewood wheel which was not on the Camaro when Sublet purchased it?
The subsequent minor modifications were made by Dana Sublet (headers,Mallory electronic ignition, replacement carb. and Cherry-bomb style mufflers in place of the Chambered mufflers).
Dana Sublet reluctantly put the Camaro for sale in 1999-2000. He needed $$$ for some family medical expenses.