It does OK. I got up to halfway on the stock gauge one time in traffic on a warm day.
Previously, it was a 19" radiator for a 318, but now I'm running a nicely built 360 so I put in the bigger radiator. On cool days, the 19" did fine, but I worried about hot days and traffic so I put the bigger radiator in.
I didn't have to mangle anything and I used existing holes in the core support. I did drill a hole in the radiator mounting flange though on the Drivers side.
On the passenger side for the bottom, I used an existing hole in the core support with a tab I made in order to extend it to clamp down on the radiator mounting flange. Sort of have to see it to understand or I can try to take pictures.
I was also able to use my stock reservoir too, but I used a longer hole because the nipple in the radiator is on the wrong side.
