MC18 bodywork should be a relatively easy fit. The MC16 and MC18 frames (and subframes) are just about the same width. I've got an MC16, and an MC18 frame, in the cupboard, but no idea where the tape measure is... but they're close!
You will have an easier time trying to adapt MC18 Mk1 (R2/4J) bodywork, as the fairing lowers are pretty much a direct replacement! The upper will need a new screen brace made, as it's significantly sleeker. You may have trouble getting the larger MC16 instruments in behind the MC18 screen.
The MC18 Mk1 tail is less cluttered than the MC16 underneath, but the subframes are easily interchanged. (I know this, as my MC16 has an MC18 subframe fitted, ready to take an 85-86 RS250 seat.) You will however need to remount the electrics, but again, if you can get the subframe, seat unit, and undertray, I expect it won't be a major job to adapt.
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Oh, and welcome to the forum, of course!
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Andy.
NSR-WORLD.COM
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