I am fortunate to own two r90s bikes, a very early November 73 bike and a 76 bike which I am in the final stages of restoring. This bike could be a good basis for an original bike, however I think there are a few issues.
The front-end should not have reflectors or gators ( USA bikes may have had reflectors )
Black paint mirrors
Enamel tank badges
There should be tape not paint for the coach lines on the front mudguard,fairing,tank and seat cowl only.
Switch gear too late
Handle bar clamps wrong- silver top flash
Handle bars do not seem quite right
Wrong volt meter
Transfers on fairing bezel missing
Dellortos should have metal tops
Black painted folk ears
Gearbox seems wrong , there should be a kick start for the early model
Non original starter relay
I cannot see inside the fairing but it should be smooth inside and show no evidence of grp matting.
My 73 bike is the bike used by BMW for their uk poster campaign and one of the first to arrive in the uk . The photos for the campaign were taken by Patrick Litchfield and was give the bike by BMW after the campaign
I am looking on my phone as away at the moment so I cannot see that clearly
Hope this helps
Byron