Technical Any difference between ‘40-48 ford spindles?

I know there’s a difference in drums, unsure about spindles and steering arms
Thanks

 

There's round and square backs, and the square take a longer king pin, both will interchange. Folks seem to like the round just for the look, but either will work just fine

 

Thanks!

 

39 / 41 are the same.
42 / 48 are the same.
the 39 / 41 have a shorter king pin than the 42 / 48

 

Pete, Are the round back spindles from 37-38 different from 39-41? I have always thought they were the same except for the mechanical vs hydraulic backing plate difference. Thanks for always sharing your knowledge

 

you are right, I was thinking in terms of the hydraulic brake spindles.

 

The reason I asked, I have an axle with hubs and drums, spindles etc. the drums are the 40-42 type. I have a dropped tube axle that is for 46-48 cars.
One spindle was bare and quite weathered, so would like to swap them out, so looks like I can do that.
Thanks again