[Ironhorse]

Curious as to the truck 12 bolt rear ends and car 12 bolt rear ends. Are they interchaneable, such as a 71 truck 5 lug rear end to say a 71 Chevelle 5 lug rear end? I'm not really sure if I am asking the correct question. Would a posi or open unit from a 3:73 truck fit into the axle housing on a 71 Chevelle? How do I tell what rear ratio is, truck has no engine/trans. but rear axle is complete. Is there an axle code I should be looking for and where? Any help is appreciated.