72 C20 drop spindles issue QUESTION

[HYPR]

As everyone is aware of the foundry that made the 67-72 C20 Drop spindles closed and it looks like from everyone that we won't see inventory until sometime in June or later.
I read that the 73-87 can be used although it requires the use of 1973-87 3/4 ton components, like upper and lower ball joints and outer tie-rods.
The questions are why wouldn't I do this?
How difficult could this really be? I mean is there some mystery trick I am missing that is preventing everyone from recommending this as a solution?

Or is the issue that the foundry problem affected the inventory and availability of as well?
Bob