B or E body Tubular LCA on A body

I have measured them and, YES, they are shorter by about 3/8 to 1/2". The shock mount is in a slightly different spot. The LCA mounting shaft/pin is a different diameter for B/E so you'd need to press in the proper A body versions.
Keep in mind though that THIS gives you WAY too much positive camber.
This stuff was done in circle track racing but those guys were willing to drill, grind, weld, cut and modify their stuff to gain that little edge.
I would advise against this.