Hi Richard. The 1mm value in the manual wont be up&down play – you would certainly know all about it if that was the case! Looking at the manual, the vertical play (radial) limit is 0.05mm (or 2 thou) – so hardly measurable.
As for side play, the manual says the conrod is “guided by the small end bush, that is why the axial clearance can be a little larger at the oppsite end”
I’d be tempted to chuck it back together