Roll Center on a GM Metric G-Frame with Ford 9" rear-end.

Hello everyone, this is my 1st post here.

For the past 10 years we have been racing GM Metric G-Frames with 4 jack screws.
We are racing a 4/10th of a mile asphalt, near flat track. Autodrome St-Eustache in Quebec, Canada.

In 2010, the sanctionning body introduced a new rule, allowing us to put in a Ford 9" in the back. So we did.
We have to use the originals hook-ups(brackets) on the frame with the original lower arms.

We are allowed to change the position of the hook-ups on the housing (open). We can use multiple hole brackets on the housing.
The upper arms are open, so we use heim joints/adjustable bars has upper arms.
Again, we are not allowed to use a panhard bar, just the original 4 points on the frame.

We are looking in a way to lower the roll center, do you have any ideas, suggestions or even a contact that could help our team out. Where would be the best position to put those hook-ups on the housing ?
We would appreciate any help in this matter.

Thank you.

2007 Nascar Whelen All-American Local Track Champion Crew Chief