[lolife99]

I’m subscribing to this thread.
I have a set of belltech 3121
spindles waiting to go on a ‘70 c10.
I checked the upper ball joint fit and it was fine.

Are you saying neither upper or lower ball joint fit?
And the outer tie rod didn’t fit either?

I remember years ago going through this same issue with another member.
Turns out the previous owner had swapped in a 73-87 crossmember to get disc brakes.
Can you post some pictures of your a-arms?