I went with the Mike Maier Inc. uppers and JRI coil overs last year, everything else in the front was stock. It's unreal how it transformed the handling and feel of the car! My old 68 had the typical 620 springs and KYB's and compared to the 66, it was garbage.
I now have the CPP lower sub frame kit but haven't driven the car with it yet. I'd look at CPP and Opentracker if you want to keep the cost down and stay with coil springs. If you're set on coil overs I'd say Mike Maier Inc. is the way to go.