The 960/4c was only one model that ran 2013 to 2021 (ceased production at Ciro in November of 2020, due to retooling for MC20 production, with a total of 9,195 units plus or minus prototypes, one-offs, and the Tributo "red carbon" final versions).
EMEA 960's differentiated from "NA" 960's in that the EMEA orders used a thinner carbotub, had much less "crash structures" and no reinforcement inserts in the subframes, and different headlight/tail light wiring and assemblies.
The Coupes differentiated from the spiders only in that the roof, rear fenders, and tonneau/"engine hood" (obviously), the "roll bar" subframe, and A-pillar windscreen frame (including reinforcement in the coupe).
These differences actually equate to just the one 960 platform with only "Trim" differences as noted in the VIN codes for these cars. The heaviest 960 is a full option 2021 Tributo at 1,133kg and the lightest 960 are the early EMEA coupes in base form and "sport" exhaust (muffler delete) and 17/18 wheels at 890 kg - both "wet weights".