Hello everyone, I'm looking at overhauling my K04s from an RS4 B5 and was thinking about just throwing RS6 cartridges in there instead. I've had a look at some technical drawings and for sure the intake turbine needs some massive work, but the exhaust I'm unsure of.

I'm wondering if the exhaust housings need machining to since the Inducer/exducer are of 50/42mm and the RS6 exhaust turbine is 50/44.5mm. If anyone's done this, I'd appreciate some tips, both for the machining and for machining shops taking on this work in Scandinavia/Britain/Germany or anywhere else I could ship them pretty simply.