Hmm. Snot easy though is it? I even read the workshop section to check, and I'm not sure I understand what you're getting at with the 'keystone' bit.
Maybe it's just the bad light in the workshop, cuz my eyes are perfect.
Or more likely the skinfull I had last night has blurred my brain!
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MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball