So now I got me a starting point. a bit of touch up paint and it's looking good.
That tank was given to me by a friend who deals in vintage british bikes and parts. The tank was lying on the floor at his place ready to be thrown out. it was no good to him so it came home with me.
It was covered in thick rust and the other side has some big dents with filler in, I'm building this fucker to be used every day. A bit of ankor wax and some tank sealant and it's good to go.