WEll, Either i missed something along the way here on this subject....or there has been quite abit of talk about this swap??? NOT saying theres a thing wrong with AMC 20 rears....All i asked awhile back was.... what Mopar 8 3/4" rears will fit my 1974 AMX! Much easier(where i'm located) than finding a Model 20 posi(complete and good shape)! Don't know what got on e lister with a 10 sec car all fired up? There are NO AMC 20 posi rear anywhere near me to be found. I looked,called salvage yards..amc folks also,,asked the list also!! So i'm swapping in a mopar 8 3/4" with 3.55 gears. I have a twin-grip/posi unit and 3.54 ring/pinion here.Was going to do the work of switching into my axle housing that came in my car.BUT was "told" that posi axles are different length..depending on year??? No one here (again..where i'm at) seems to be for sure!I also have a 1969 Mustang 9" housing...just incase i feel like swapping that instead. I MAY use the twin grip setup in my 69 Jav housing..in my Gremlin..if SOMEONE can tell me whats up with axles? Hope i didnt start something...crimany sakes. Thanks alot, Joe __________________________________ Do you Yahoo!? Meet the all-new My Yahoo! - Try it today! http://my.yahoo.com