**********PROBLEM SOLVED**********
Well took the car to an engineering firm this afternoon and what can I say they did absoloutley everything! I was prepared to strip off the SC induction pipe, and remove the SC bypass pipe, and remove the brace, but they did the whole lot. Stripped it, welded it, powdercoated the weld, and put everything back together again. They disconnected both terminals of the battery as there is a risk of frying electronics when welding. The guy said something like it can reverse the polarity of the battery if the terminals are left connected while TIG welding. I didn't fancy forking out for a new ECU so disconnecting the battery was the first job!!
They removed the brace and when the took it away the little piece which the brace connected onto at the cradle came away too, surprise surprise. They used sandpaper and sanded down the area on the cradle where the piece broke away and then TIG welded it onto the cradle. They opted for a TIG weld as it is a much more substantial weld than a MIG weld. After the weld had cooled, they actually took the trouble to go and spray it with a black powdercoat paint. It was a nice touch and you'd never even know know that a repair was done. Just as a matter of interest, the welder commented on how shoddy the original weld was! So anyone else out there with the SC, it might be an idea to check the weld at this point, as if it was as weak as mine, you'll be in the same boat as I was with that very very very annoying rattle.
Dont know if people are interested but I took a few photos of the repaired weld.
CRACKED WELD
TIG WELDED REPAIR