| OK...I know what you mean Paul...I'll give you my thoughts on this.
Having bought my 1995 SP I made a few enquiries to Ducati Italy to clarify exactly what model I did have.
After passing on the bikes details, I received instant confirmation that it was a 916SP.
The lady there was also kind enough to send me data sheets for both my (1995) SP model, and the next years (1996) 916SPS model.
The diferences are with the engine...
The 916 SP has a 916 engine, making 131bhp with an rpm limit of 11,500.
The 916SPS has 996 engine, making 134bhp with an rpm limit of 11,000.
The 916SP3 that is often mentioned is the equivalent of the 916R in the chart that henners has listed in the above link (scroll down a bit!)...a bike produced at the same time as the 916SP only, but fitted with a 955 'kit' to go racing, I believe in the US. Thas why a 916SP can easily be fitted with a 955 kit, as essentially it is the same bike.
mmmmmmh...now theres a thought, wheres that phone No. for Sigma! | 
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