Trying to lessen (or is it worsen) the mild controversy over AMC/Rambler front spindles, I figured I'd start compiling data here.

Here's what I believe is the general consensus on AMC/Rambler spindles:

• All AMC and Rambler-badged cars use the same basic spindle design back to Nash days: Any AMC/Rambler spindle will bolt onto any AMC/Rambler and most if not all Nash and Hudson back to 1950. (Thanks to Frank Swygert for this information.)
• There are two variants of this "regular" (sic) spindle, called here Tall and Short, and this is the subject of this web page.
• All cars that use the "regular" spindle use SET2 and SET6 (aka A2 and A6) bearings. The grease seal is the same on drums and discs.
• There is an additional variation, that apparently applies to AMC 1975-1976, and 1975-1978 "big cars", which use different bearings (A16 (outer) A17 (inner)) with the "big Bendix" brakes. These are decidedly less common than the regular spindle and no more will be said about them here. (Thanks to Andrew Hay for these details.)
• All "regular" disk rotors and all drums and hubs seem to fit either spindle.
• Any spindle bolts onto any AMC/Rambler steering knuckle.

HOWEVER (you knew there had to be a catch):

• Certain combinations of car, brake and spindle collide with the steering knuckle. For example, putting disk brakes onto a 1970 AMC Hornet that came with 9" front drum brakes, the disk brake dust shield hits the spindle unless you use Tall spindles, which space the brake parts outboard.
• The good news is, if parts don't collide (it's quite obvious) there are no other problems.
• The controversy, if there even is one, revolves around which cars came with which spindles, Tall or Short, and why. And the Yeti in the mix, are there even other height spindles? Are such things even possible?
• That's it.
• Tall vs. Short spindles change the front track of the car by the spindle height difference (OK it's spindle width, but I measured the spindles sitting on a table, I just hope you can deal with this difficult abstraction).
• Tall vs. Short spindles affects the fit of the wheels, increasing setback tolerance.
• Changing spindle height (width...) will also affect camber. Have your car aligned afterwards.

There's more!

• In general -- drum brake cars come with Short spindles, and disk brake cars come with Tall spindles.
• THERE ARE SUSPECTED TO BE MANY EXCEPTIONS.

The moral of the story is:

• The best donors for putting disc brakes onto AMC/Rambler cars are the Bendix systems or possibly the early 80's low-drag brakes. (I don't have tablulated year/model details.) Conversely, avoid the earlier Kelsey-Hayes systems (fine brakes; pads are easy to get, rotors hard to find).
• If you pull disk brake parts from a donor car to swap onto your drum-brake-equipped car, take the spindles too.