Hi Steve, I have heard this before" you need to replace the entire centre as they arent rebuildable".....
It is simply not true, we get cores upgraded all the time.
I concur......A friend of mine owns a shop in japan and he offered to rebuild a clappered 2530 turbo i had for a tad over 70,000 yen....i then spoke to a few turbo guys in aust and they said you have to buy a new core....now i am thinking that maybe coz of the high use in aftermarket turbocharges in japan they may offer a better parts back up system than what we have in aust....just a thought