Dale,
The metgas was 1179 and the SAR is 2554. There were differences between the different manufacturers which is quite noticeable especially when you look at things like the welding and some of the fittings or mountings used. In the "Workshop Repair and Maintenance" manual in the electrical section there is even a note on the wiring diagrams warning that it does not apply "to many of the carriers built by the South Australian Railways" and refers to a supplement which I haven't seen. (Does anyone out there possibly have a copy?).
In the "Carrier M.G. Instruction Book" electrical section it mentions that approximately the first 2,700 carriers produced were wired differently because of different generator set-ups used. Then goes on to say "with the universal conduit lay out now used............" and explains differences with the later production carriers.
Also, does your carrier have a 6 volt battery or like some carrier owners have done, have a 12 volt system. All up, there is quite a bit of variation there. When I get around to doing mine I will probably go for a 12 volt system and as long as everything works, is safe, everything is securely out of the way and it looks tidy I will be happy. (Apologies to the purists).
Pete