Daily driver? 351W or stroker such as 393W gets my vote. Cobras then, and now are notorious for overheating. But not with these Windsor motors.
You don't need an
oil cooler, but a good baffled 8 or 9 qt pan such as Canton road race provides plenty of
oil, and keeps it in the
oil pickup. I use Castrol Syntec, but any
synthetic gives good high temp protection.
351W motors very tolerant of high ambient temps for street use but cooling system needs first rate parts. Spend the money here for better than OEM components. Big, heavy duty, aluminum radiator; hi vol water pump, street rod ratio pulleys, healthy electric fan. Can run 180 deg thermostat year round. Once the car is going over about 30 MPH, there is enough airflow through the radiator so the fan doesn't come on at all.
Ceramic coat your exhaust system inside and out at least headers, and "J" pipes back to the mufflers if you can get to them.
Second summer in DC rush hour traffic (95+) plus road trips and events and absolutely no hot running or overheating problems.