[30fathoms]

I believe you're correct, just a ball joint swap if you keep the lowers; however, if/when those lowers give up, it would be much easier and cheaper replacing the newer component. Having all components from the same year was a big factor for us. For example, the older inner TR and newer outer TR (needed for the spindles) are different sizes. There is an adapter adjusting sleeve for the TRs available but that builds in an "odd" part that may be a bit harder to find when replacement time comes.