Bonnie 1200 Engine Cases Daft Question Alert...!!!

So.... although they look absolutely stunning when nice and shiny new, the bare brushed alu' engine cases are a bugger to keep on top of. Which is why I'm thinking of getting a spare set to keep nice and clean and swap them over when I need to (for what ever reason that may be)

Question is... Although they look it on the outside, do the engine cases from the Thruxton R fit the T120 or are there any internal differences that would require any machining etc.? Only asking as I have a chance of an unused set for a good price off a Thruxton R.

Any advice is greatly received.

Cheers
Bunji