It’s interesting to consider the world market of the period, in that with the 120 FHC, they made 2483 LHDs (mostly for the US) and only 195 RHDs (mostly for the UK). The goal required by Sir Stafford Cripps was 50% exports, so perhaps this helped to balance out some of the other models such as Mark V, of which there were more RHDs.
S669195 is an exceptionally well restored XK120 FHC and would thus suit many buyers…
But its not by any means a reliably original car, so I would be very careful accepting any detail of this cars build/restoration as proof of originality detail, in both major aspects and certainly minor aspects.
The car currently has an XK140 1955 era C-type Head fitted, with no proof/evidence at all as to what Head was fitted originally, that was the basis of my extensive interest some years ago. And indeed after its restoration which included having this XK140 Head fitted, it was also then fitted with standard H6 carburetters, so again indicative of its current status that it now has ‘sandcast’ H8 carburetters fitted, whether Burlen reproduction sandcast H8s or less likely original-XK140 optional ones I cant tell without better photos, regardless, not original to this XK120.
See photo after its initial 100% restoration/rebuild… note the H6 carburetters then fitted