i have a 69 mustang with a 351w. as far as suspension, so far i have rebuilt the front end with a polygraphite kit from pst, and installed kyb gas adjust shocks front and back. it handles noticbly better but far from what i want. any suggestions on what i should do next?

i am not familiar with the "polygraphite kit from pst", but if it does not include new springs, I would add those. As well as any type of aftermarket sway bars. Sometimes the steering boxes get pretty loose, so that may be worth replacing if you get a lot of slop in the steering. Tires and Wheels make a huge difference. All these things add up to make a big difference. I put a new rack in one of my late model mustangs a few years back and could not believe the difference!!! Didn't think it was that loose before.