I can see why this can get so confusing on the carrier/case side of things.
For years I have called the bit with the spider gears in it a carrier or hemisphere but as posted before, in all the Holden books I have it is called a case.
So the correct Holden name for it is a case.
So from here on in I will call it a case.
This is a problem I come across on a lot of parts because different manufactures have different names for the same item.
Now as already stated on the cases there is different banjo case for 2.78 and 3.08 compared to the case for the 3.36 3.55 qnd 3.90 ratios.
Just to confuse the issue a little bit the Salisbury cases are 2.60 and 2.78 run the same one and 3.08 3.36 3.55 and 4.44 use the same case.
The reason for the different cases can be seen here
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The sheer size of the 2.78 and 3.08 pinions necessitates the different cases but as stated above this can be overcome by spacing the 3.36 etc crown wheel over on the case.
Now from memory the carriers are also different as well.
Apart from the 2.78 and 3.08 carriers having the long two bottom bolts they are also different to allow for the sheer size of the 2.78/3.08 pinions.
Also from memory a 2.78/3.08 pinion will not fit in to a 3.36 etc carrier.
But a 3.36 etc pinion will fit in to a 2.78/3.08 carrier.
I will think on this all as I keep getting a flash of memory that makes me think that some of these things can be miss matched and it will all work one way but not the other way if that makes sense.
Cheers Paul.