I got a 2003 KGT as new 'take off' from the States and put that on my '97 KRS. Many buy these bikes and want lighter and a different sound, so buy aftermarket.
My header flanges were so badly corroded (NOT stainless steel) that I was not going to mess about swapping bits over. I did open up the old can just for kicks with an angle grinder. As others said, rusted in bolts are a pain.
If you buy a clean take off from the States (and quite a few come up), check the seller has the right facilities to pack and send. It is doubtful that a private seller could do it. I went through a bike parts seller (like UK Motobins) used to handling international shipping.
Shipping from US would probably cost you as much as the selling price, as the system is in one piece, very heavy and needs contorted packaging to protect the headers and muffler sleeve, It is very nearly a small crate job. Use DHL/UPS etc. Do not even think about el cheapo surface mail ending up in Mount Pleasant UK, else you will have a ££ surprise on arrival!
If your headers and the pipes to the CAT are all good, then you will not want the uncertainty and pain of import. Either buy a nearly new complete system from UK, or even a new sleeve at Stealer prices may work out cheaper.
I like my stainless polished sleeve. I have gradually been replacing most parts that go bad on the finish with stainless. I am a lazy 'wash and go' guy who hardly ever gets the polishes out!
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