Thought this may be of use to someone
Happened to be at pick and part today and they had a c30 R design there, a mate bought the seats for a ridiculously cheap price and it was almost a straight bolt in for the 240 .
We removed the c30 seat rails and the 240 rails pretty much bolted straight to the seat , the rear needed a couple washers and a longer bolt to be the right width , it keeps the 240 manual slider , that's as far as we got need to figure out what wires do what to power the recline function and I'm guessing heated seats will be able to work as well
They fit really nice they are a good width , the seat base is a great height I'm not a fan of the headrest and they sit about an inch higher then the 240 headrest but overall it looks quite neat , bloody comfy seats too ..
No idea what year model the c30 was it was missing the whole front end but apart from that looked brand new and had 70k on it .
These are the only pics I grabbed while I was there .