DIN adaptor for my Legend Reg arrived and lawrence from SPLASH again sorted it out for me,many thanks.
That coupled up with my lovely shiny new THERMO valve on the tank its looking mean..
Heres the final edition that I am 98% happy with,the last two are:
a) As Tara rightly said the round type of bungee's roll and move so something flat and rubber like inner tube would be a go.
b) The second stage doesnt hug the bottle at the top as well as it did with the yoke so the second stages flops around a bit,which I really dont like.