Have been trying to sort out what the various suffix letters in the SIIB actually mean.

I have a South African 1974 build 332 prefix Suffix F. This vehicle has SIII 1 Ton all synchromesh gearbox (low ratio all helical transfer box) clamshell chassis rails and Salisbury diffs.

Jeff Smith has a 1972 Australian Compliance plated UK build 331 suffix with ENV diffs and all synchromesh gearbox.

I haven't sorted out the difference between my 1969 UK build 331 suffix B and my two 1967/1968 UK build 331 suffix A but I suspect the difference is the 569203 negative offset rims in place of the 543384 rims of the SIIA FC and early SIIB FC.

Would like to know if anyone has the explanations from the Rover Service Bulletins or from their own vehicles?