In short, get a 26"w x22"h x3"thick alum rad with 1"-1 1/4" tubes, 22 or so fins-per-inch & 2 elec fans that will pull as much air as possible. Use Evans coolant, and an alum waterpump and you should be set. My 528 Hemi has this set-up & it seems to work.
This can get technical so I suggest you talk to a rad. MANUFACTURER first, not just a supplier, and get their input.