My 600 is about as stiff as a wet noodle.
I'm not talking about "oh, it'd be better for auto-x"; I'm talking about fear of metal fatigue after a few years of just cruising and driving. Car's going to have to get torn apart lots this summer anyway, so I'd like to maybe stiffen it up while I'm at it.
I'm thinking that strut and shock braces will be a nice start (to avoid twisting around the car's long axis), but something more will need to be done. I want to keep the car stock "looking", so a rollcage is right out.
Where are other good places to think about adding supports?