I believe anything with a 3" saddle will fit. Or, at least I 'think' it's a 3" saddle. I recently took off the factory Cat plastic skis on my ZR, and was contemplating putting them on my Formula, so I did some measuring.
My buddy put plastic skis off a '98 ZR on his '94 580 without a problem, so those would have a 3" saddle, and that EXT should be similar. I would think if you go with Cat skis, they should fit with little to no modifications. Don't quote me on that though.
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