Hope this helps as far as I can see on the MC21 version it’s the shape that’s changed and the length of the HT cable from earlier MC18 coils (rear lead needs cutting down)
Apologies for quoting myself but it seemed a bit daft to post a link and then expect you to go and find the post in my rambling build
Wayne_Gardner wrote:
Then you get onto the HV coils the new ones that arrived have rounder bodies with a slot – MC18 coils are more 50p piece shaped hence the difference in part number(s) so the rubber holders don’t fit, however I got round that by buying the later MC21 retaining rubbers which understandable are a perfect fit - peace love and harmony being restored after a little more wallet waving at the problem!
Pic borrowed from Mr Google of MC21 holder
:
All the best
Nick
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Nick
Rebuild project NSR250 MC18 R4J