The Scimitar kit. I don't think it really matters. At the time, the Scorpion kit was harder to find. I would think that any Sabre in service(at least in KFOR) would have the late sprocket style.
After reading the Darlington book on Scorpion/Scimitar, I did mate the Sabre parts with an early Scorpion upper hull but only because I had the upper hull laying around. I don't think it matters that much visually.
The white metal barrel that comes with the older resin is on par if not better than the resin barrel in the grey resin set.
The second from the right is my first buildup of the Sabre. My cream resin set was missing the corrected commander's sight.
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I think the PE headlight guard is from the Airwaves set.
Paul