In 1983 Aurora produced their last catalog and distributed it February at the annual New York Toy Fair.  Several new and exciting items were introduced including a MASH Set, Fire Engine Set, and these infamous Super G+ cars.  The file photo on the left shows the intended set exclusively for JC Penney's.  It is widely believed that only a dozen sets of these cars exist as Aurora went bankrupt in the spring of 1983.  I know of (9) sets and they all were given to top performers for Aurora and never sold at retail back in 1983.  I have owned (2) sets having been collecting since 1987.