Luckily the seats are authentically intact and as squashy, enveloping yet properly supportive as only the French knew how back then. Once you're in the driver's seat, you never want to get out.
It's best, then, to examine the 304's outside bits first. Its nose resembles that of the larger 504, with its giant trapezoidal headlights. The boot is vast, mainly because this is a two-seater car which could quite easily have been a four-seater. Under the bonnet is a little overhead-camshaft engine generating a healthy 75bhp from its 1288cc. No wonder there's an 'S' on the tail.
The engine bay repays a closer look, because the 304 does things differently. The battery is down low, behind the bumper and next to the radiator, in front of which is the jack. The fan is directly behind the radiator, as you'd expect, but the engine is mounted transversely. Which means the fan belt has to do two extraordinary right-angle twists, but contrary to expectations it never flies off its pulleys.
It's 8am. We're leaving the delightfully welcoming Château de Germigney at Port Lesney, which is nothing to do with the manufacturer of Matchbox model cars. The 304's roof is stowed, of course, and we're heading to the peppermill factory at Quingey. Straight away the 304 feels eager on the throttle and fluid in the gearchange, the whine from its transmission – in the sump, like a classic Mini's – singing exactly the same note as it did in the Peugeot 104-derived Citroën Visa I once owned. Every carmaker has its own specific sound signature to its gears, it seems, depending on its traditions of gear-cutting techniques. You don't hear it much in modern cars, of course.