Drum vs Disc Spindles

[gzig5]

How do I tell the difference between drum and disk spindles, and I think there is a difference between early and late disc spindles too?  I have a set of spindles that I don't know what year or style they are.  Like to use them to mock up some brake conversion ideas, but will need to get the right bearings and rotor.   Don't feel like tearing the car (1973 w/disks) apart to compare them

[bc3j]

 Not an expert by any means, but thought the inner bearing is larger. Outer bearing is the same.

[JS29]

I am no expert ether, but i do know drum and disk brake spindles are different. early and late disk brake spindles use a different size barring. I think it's the inner that is a different diameter. I believe 1973 disk brakes were mandatory. Aftermarket disk brake conversions use an adapter to mount a caliper to the spindle of the drum brake equipped cars. I don't know is my rantings help answer any of your questions, I hope they do.    

[anlauto]

Drum brake spindles have four bolt holes in a trapezoid shape. Disc brake spindles, have two on the bottom, and two off to one side.

[dodj]

This might help
https://www.performanceonline.com/1962-74-MOPAR-A-B-and-E-Body-Disc-Brake-Spindle-Kit/

[gzig5]

Well, they are definitely disc spindles which is good.  Now to figure out which bearing they take. I think I kept the old bearings from my rebuild last year so that should tell me.  I can turn up an adapter bushing if they are the smaller diameter spindle and that should work for mocking up the caliper and brackets.  Now to get to work!   
Thanks.

[bc3j]

Take a look at A17 inner and A2 outer. I used Timken bearing sets when I put 11.75" rotors on. I knocked out the races that came with the rotors because they were the Chinese steel type and used the Timken bearings and races instead. I think the drum spindles use set 6 inner and set 2 outer.

[BFM_Cuda]

72 and up disc spindles.....


Good parts list for the disc swap:

https://www.allpar.com/history/mopar/brakes/disc-parts_list.html

[JS29]