From the top of my mind, there are no real changes between 85 and 86 models, on those years the interior had already been changed (sun roof was available *here in Peru I´ve seen 82s gtv2.0 and gtv6 eurospec with sunroofs*, seats changed in 83 with the Recaros) and the shift linkage was redesigned in 85 so that´s all there is. So te mods you recall must have been aftermarket.