12 months later, nearly, and it seems that my memory has grown fuzzy over the last 35 years.

Whilst I remember, and played Total Eclipse (and it looked like a promising contender), and Marble Madness was fun, but as far as I remember, no prize, it was neither that I was thinking of, and I got the prize wrong.

The game I had in mind was Gyron, which had a prize of a Porsche 924 or £12,500 cash for the first to complete.

I'm so happy to have finally cleared up this mystery. :)