Small block radiator size/cooling issues

I've just swapped a slant six for a 360 small block in a '69 Plymouth Valiant which had factory a/c. I assumed the radiator was heavy duty enough to handle the cooling issues because of the a/c. so I kept the original radiator, fan and shroud from the slant six. I have a March bracket/serpentine belt system on the small block along with a compact sanden a/c unit and power steering. New motor has headers, a mild cam, electric fuel pump, auto trans w/stall converter, rebuilt stock cast iron heads, 600 cfm carb etc. I'm not drag racing it so the fewer ponies were an o.k. compromise for the convenience of ps and a/c.The water pump is a Mopar high performance 8 blade. The radiator measures roughly 23 inches square and has the #2949072 stamped on the top and #38086 stamped directly underneath. The car runs hot. 190-210 degrees in 80 degree weather with a 160 degree thermostat. Is the original slant six radiator too small? I've seen similar radiators on some big blocks and even hemis. I don't know if it needs to be re-cored or replaced with a larger one. I would like to keep the stock look as much as possible. Maybe a re-core with an aux electric fan? Anyone have any thoughts or know what applications this radiator will work with?