O.E. rear end would have a round cover & the 3rd member bolts into the housing.
2.08 would be about twice the speed of o.e.
Remove the rear cover, should be markings on ring gear, smaller # is pinion teeth, larger number is ring gear teeth. If no marking found count teeth on ring & pinion, ring gear teeth by drive pinion teeth will give you the ratio.


BC
1960 Chevy C10 driver 261 T5 4.10 dana 44 power loc
1949 GMC 250 project in waiting
1960 C60 pasture art
Retired GM dealer tech. 1980 - 2022