So if you already have the axles, why not just pull out the old ones that are in there now and compare measurements? If the new mosers are two inches shorter take 2 inches out of the housing.
I originally ordered the Axles at standard measurements, but put a hold on shipment under the housing is shortened. I would be very happy if I could find the factory offset for A Body Diff's. I know what the offset is for the Rear I'm trying to put in. Hopefully I can get under the car this weekend and pull the old rear and get the final measurements.