Tonybanks or Keltec, Both in Leeds and both highly rated, I was quoted £350 for a full 3" mandrel bent stainless exhaust from the decat back with a custom backbox by Keltec.
Seen the exact same guy selling the box on the facebook pages and exactly the same thing happening, Bet he's made a pretty penny ripping people off. Seen him trying to sell a roll cage that looks like its been welded up by stevie wonder
Empty a bag of big nuts into it and shake it around then tip them out and clean them and repeat. That's what i did with my RX7 fuel tank and it was sweet afterwards!