Difference in 1/2 ton and 3/4 ton Spindles

[WB72]

I would like to lower my 1972 3/4 ton 3 - 4", but I would like to keep my 8 bolt pattern.

Will the 1/2 ton spindles hold 3/4 ton rotors? (I will not be using this as a 3/4 ton truck any more, just a grocery getter)

I thought that someone posted there is a way to do this by changing ball joints to different year (73 up). Is there any truth to this?

I would like to be able to find out from someone who has access to both spindles. to measure the spindle part.

If the axle part is different dimentions, would it be possible buy different bearings and races for this application? Someone in the bearing busness may be able to check this out if I could get the dimentions.

Thanks for your help.