A-body LCA 67-72 vs 73-76 differences?

So why I want to weld on my own is because the tabs are at the end of the arm. Most aftermarket bars use that bolt in "L" bracket at the shock bolt which is inboard of the factory location. I want to use the factory location because that LCA sway bar mount location is like a cheater bar. The further out you apply the force, the more leverage you have.
because you have a 73~76 set up already, i'd recommend sourcing some factory 73~76 LCA's with tabs and then procuring the factory style bar of your choice-- which there are ample choices from many aftermarket companies.

the effective wheel rate difference between the two bars pick up location isn't enough to worry about unless you are building a full competition vehicle.

the problem with the hotchkis stuff is that it's designed to really only work with their system, so you're kinda beholden to them as far as bars go. and some people don't like how forward and low the bars mount.