I have no idea as far as who made them. Wouldn't you think if you are trying to stiffen the rear shock tower's, wouldn't you want the towers tied together than the top of the shock's going thru a heavy corner & dealing w/ the force going thru the bushing's whether poly or not? It might be a little more hasell to install, but then it'd be stiffer.
Introduce Mr. Torsen to the mix
D23 crew- D-Tech- Sedan Revolution= #131