To get the gearing we want in a early Ford rear axle, we had to get a Quickchange centre section. For those unfamiliar with this: it replaces the centre section of a early Ford rear axle. It has a horizontal shaft, going from the front (power in) to the rear, through a set of gears, which are available in all kinds of ratios, and back in the differential.
We managed to get one on ebay for a reasonable price. Turns out that seller Jim lives 110 miles from Bonneville, and he is a regular visitor ! Besides that he owns a KILLER 34 coupe, one of the very, very best I've seen. Nice guy !