Basically, as long as the clutch disc and the flywheel are matched, you can run whatever kinda clutch you want from a K-series engine.
If you're running an Si-R clutch, you need an Si-R flywheel.
If you're running an ITR clutch, you need an ITR flywheel.
I'm not even sure if the Si-R has a different clutch setup from the USDM Si, but you get what I'm saying; keep the clutch disc and the flywheel matched, and you're good to go.
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