Hello "END CAN".

First off, would you mind NOT posting in capital letters. In open forums such as this, it is considred as "shouting" - a way to get a point across to others.

Back to your problem. I am afraid there is little or even no chance of getting the MC21/28 shock to fit the MC18. The frame mounts are just far to different. Your best option is to try and locate an MC18SP shock and use that instead. You may find a 1989 RS250 shock may also fit, but they are rarer than hens teeth, and you would still need to measure it, just to be sure. (The MC18 shock is the only one that will be a definite "bolt-on" job.)

Andy.
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