Keep hearing about frame twist with 440s

I figured it should have weight on it based on what I know about suspension but I don’t know if it should have the weight of the 440 or the slant six. I want to say using the slant six weight is preferable but I really do not know.

The problem w/ this is , are the springs / strut rods and everything all settled/worn the same ?
Will it change later if you have to do something diff ??
I`d rather have the car leveled on jackstands and take the suspension out of it .