Tony, I also say the C-4 is the way to go. It will soak up half the power of a C-6 and it's really light! I run a C-4 in my mustang, 3600 stall reverse manual valve body and a trans brake with 3.73 gears in the rear. On the not highway it's not too bad.... but not for a daily driver, too much stall. Also it WILL sound like a motorboat if you go with to high a stall. Since you have the 351W you will need a 28oz. flexplate and the tooth count will depend on the bellhousing, big or small.
