One thing I do remember is that the prop-shaft was a bit longer in the R2000 as fitted to the three's than in the standard engine so the propellor stuck out a bit more away from the cowling.
Not necessarily the propellor shaft.
The nose case on the R2000 was 'longer', hence the propellor was slightly extended.
The reason the nose reduction gear case on the R-2000 was 'longer' than on the R1830/1820 was because...it is a double row engine.