Sandman's had the same diff ratios as all Holden's available.
Typically you would have 2.78, 3.08, 3.36. 3.55 and 3.90

The tags normally give up the ratio but will not tell you if they were limited slip.

GV3 = 2.78:1 Salisbury (HQ had different Codes between Salisbury and Banjo)
GU4 = 3.08:1
GV4 = 3.36:1
GV7 = 3.55:1

I'm sure others will add to this and correct anything I may have wrong.