We're told that John Serro liked them on Shasta and so decided to add them on his Scottys. The only year they show up in advertising is 1961. But, a brochure from 1968 still lists them as optional. We are also told that Shasta didn't like Serro copying their idea and threatened to sue and Serro therefore stopped advertising Scottys with wings.

We are told the wings were created using the material cut out for the wheel well swooshs. From the looks of these pictures, that seems entirely plausible.

Here's 1961 advertising:

And here is a 1961 Scotty being offered on Ebay (6/2008):

And, this is a 1964 Scotty being sold in Canada in 2006 with wings:

Ian had his wings made by Tyler Bessette, the Shasta wing guy.

Zina added these wings to her 1962 Front Kitchen Scotty