hi, gz again:) i have the 79/80 AMC parts catalog. Parsing it, it says the the EAGLE rear axle could take the 3:08, 3:31, and 3:54, though the books tooth count for 3:54 is confusing (11/39 which is the Amc 20 count) instead of 13/46 which is the Amc 15 count. (according to this book) However, looking at the Spirit/Concord rear axle, same part # for 4/6 cyl. cars, (though different from Eagle), book says axle can take any gear set from 2:37 to 3:58. Why would the Eagle axle housing be any different? got my fingers crossed on this one!
So, extrapolating a bit, if a 3:08 fits where a 3:54 goes, and the 2:73 goes where a 3:08 goes, it should work in a 3:54 case. If the Eagle housing is same as Spirit/Concord housing, then any gear set should fit. This would really solve my problem. Maybe most of the gear incompatibility issues regard the FRONT axle, not the rear? Thoughts? thanks, gz