Right, got bike out of shed, shock off.
I presume your shock came with the 'sleeve' bit. i.e a central 'shaft' on which spacers/washers sit either side?
Ok,
Top end (Main frame);
Width = approx 22.57mm
Inner diameter/bolt hole = m6
Shock sleeve hole = 12mm
Width of shock mount = approx 11.8mm
Rear end;
Width = Approx 47.45mm
Inner diameter/bolt hole = m6
Shock sleeve hole = 12mm
Width of lower shock mount (stanchion end) = approx 11.8mm
About right?
Is that enough to go on?
Dont forget there are little rubber seals before the washers go on the sleeve.