I have been offered knuckles from 1990 & 1996 South African vans to
convert my 84 Caravelle to later brake-fittings (in order to fit the
Porsche 993 brakes).

Does anyone know whether the RSA knuckles have the same caliper
mounts and bearing sizes-offsets/spacings as the later German items
ie would 1986+ German hubs & calipers bolt onto South African
knuckles? I suspect not...