BRAKES WHAT'S NORMAL

[Timothy P]

From the index cards, also on the magnificent archive site LINK, which provides part numbers as well as the 'reference number' found in the parts lists.

1926-1932
Offside cam front - Reference number: BL31 - Part Number 1A4032
Offside cam rear - Reference number: BO66 - Part Number 1A4032
Nearside cam front - Reference number: BL32 - Part Number 1A4033
Nearside cam rear - Reference number: BO67 - Part Number 1A4033

1932-1936 (change given is the introduction of the wider drum and shoes)
Offside cam front - Reference number: BL76 - Part Number 1A7194
Offside cam rear - Reference number: BO149 - Part Number 1A7194
Nearside cam front - Reference number: BL77 - Part Number 1A7195
Nearside cam rear - Reference number: BO150 - Part Number 1A7195

So front and rear on a given side should be the same for pre semi girling systems. What the change in the cam was between the 1" and 1 1/4" systems I don't know.
The early parts lists only give reference numbers, and as the front cams appear with the front axle parts which all have BL prefix, and the rears with the rear axle parts all with BO prefix it confuses the fact that they are actually the same front and rear. Other parts are similarly effected with the different 'reference number' despite being the same, drums shoes etc.

Bob these are the only 2 sets of cams given, before the semi girling system. The last parts list to cover the pre girling system, as far as I can tell, is 1406A available on the archive site referenced above. This one also includes part numbers, and these along with the reference numbers, match the second set above.