For towing I might think something around 224 @.050 with that head should work well. Keep it a fat mild ramp with a relatively mild spring and let the crank arm do the work. I still like a fairly tight centerline so the torque comes on hard for inclines, etc. Something like the old Isky or Lunati 4x4 grinds would work well. Lunati used to have a 228/235 Truck cam that was pretty stout for a 360 but would be about as aggressive as I would go for that combo, it's got to be able to pull a tight converter out of the basement.