Lateral location of rear axle

[97snakedriver]

The lower control arms don't do much of anything for lateral location. They're at a 90 degree angle to the direction of the motion you are trying to control. Its like tying to hold a weight in your hand while holding your arm straight out. That's why the upper control arms are at an angle.

The best way is the panhard rod/torque arm setup. With that setup the control arms (panhard rods and torque arms) are located on the same line as the motion they are trying to control. The torque arm keeps the axle from rotating forward, the panhard keeps the axle from moving laterly. Instead of holding your arm out straight, its like pushing something away from you like you're bench pressing it.

You're 4 parallel and panhard combo would do about the same thing. I guess it depends on how well you can fabricate it and how much it will cost to do it.