This piece of work is by the AUA (Ardler United Artists).The fact that it's part of a Kingsway flyover means it would be a pretty tough venue to get this done, having to avoid the volume of passing traffic. A couple of night-time commando raids needed to accomplish it no doubt!
The graffiti was put down around 1984/85, but after all that effort, in the end, the artist got busted for it!
Big thanks to Lyken.