One amusing thing can happen with Lister Ds ,there is a parrafin (kerosene) version ,there is a vapouriser built into a small manifold where the exhaust exits the block ,the carb is also mounted on this vapouriser block to get maximum heat from the exhaust the inlet and exhaust passages CROSS over in cast passages in the vapouriser block,so carb and exhaust are in effect swapped over from their normal positions.Friend restored one of these engines and when he timed the valve gear he took the inlet valve to be inline with the carburretor when in fact he had timed it to the exhaust valve,took an awful lot of winding before he realised it was the exhaust valve in line with the carb.
Years ago probably 50 there was an article in MOTOR CYCLE SPORT magazine with photos of a motor cycle with front and rear wheel drive.