Britannica is dead wrong, they have the M-47 as the first US made tank with a LRF, this is not true, the first American LRF was on the M60A2 Starship, plus no leopard 1 in German service got a LRF until the 1980's, the final German army version the 1A4 had a stereoscopic system.
Pakistan's most modern M-47 (in fac tthe most modern m47 ever built) the M47M was created after the 65 war and was upgunned to M60A1 standards with the same M68 cannon and co-incidence range finder, it never had a LRF.
As has already been discussed no M-48 before later A5 in the mid to late 70's had a LRF, a decade or more after the 65 war.
The First LRF in the world is the Chieftan followed by the m60A2
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The Centurion got a LRF in 1978 in South Africa as the Oliphant Mk 1