Well, to be honest. If you have the standard starlet backbox on there its just a case of removing the old box and bolting that one in its place using the clamps that came off the old one. Thats what I did, just a stright swap over, no probs at all. £100 to have it fitted? Way overpriced. The rear pipe on that box is the same as the standard one so it will fit onto the rest of the system perfect. It really is a case of just taking the old box off, its clamped on exactly the same and putting the new on with the clamps and things that are used on the standard one. Thats what I did for mine and got it fitted free, handy when you know a mechanic. No need to buy anything, just take the old one off and put that one on. Enjoy the nice sound of the TTE rear, its a beut!