[DanElam]

Don't guess on the tire pressures or try to use chalk. (Use chalk for suspension stuff, but not for tires.) Borrow (or buy) a tire pyrometer. They tell you exactly what you need to do for your tires. In many cases, it can also help you make adjustments for camber. But for a particular setting, it will tell you very quickly how to get the pressure straight. Until you know you have the pressure dialed in, you are wasting time on the other stuff.

Springs are a common problem too. A lot of cars have too much spring which lets the car hop. If you've got some unusual engine combination, it's not hard to result in a need for spring settings that are different from someone elses car.

At the end of the day it might just be you have too much HP for your tires. My guess is that 351W puts out gobs of power. From the pics, I can't see what kind of tires you have, but I am guessing street tires.

You might be able to adjust your apex a little early and learn to slide it through the corner if you are always bringing the back around on a late apex, but my guess is that it doesn't matter.