So with your new camshaft and liters installed (or in some cases where the lifters were changed on a good used Camshaft) you would need to do a Cam Breakin. i.e. Wear in process of these two new sets of parts to each other. This consists of running engine without stopping at about 2000 to 2200 RPM for 20 to 30 minutes. Set up the Carb's Curb Idle Screw on the throttle linkage so it can maintain that Higher RPM. Also first try to get all of the tune up settings very close before you start it like Plug Gap, Point Gap, & the Base Timing setting, so that it runs good enough to compleate the break in. Check the engine and its cooling system during the breakin for any coolant leaks, and that the Thermostat is opening up I usally leave the Radator Cap loose or off so i can watch for this as well as seeing if there is good flow through the Radatorcs core tubes. Also check for oil leaks too and try to take care of any of these that could come up like if its only a loose hose clamp ect. If it's a more serious like a bad Rad. or Heater Hose problem or a really bad Oil Leak you then would need to shut it down and repair it as needed before finishing up the breakin procedure. This is why personally I would mostly just use plain water in the cooling system untill the breakin procedure is compleated and I know that all the parts are in good working condition, Distilled Water is really best to use. Also check the Oil Pressure and Engine Temp during the engine breakin procedure.
Now after finishing that go over all your tune up settings again to really fine tune it, and if the cooling system is in good working condistion add in your Coolant choice. ie Anti Freeze Water Wetter etc. Some people will change the oil and filter after the cam breakin and many will wait until they have about 500 or so miles of use. Cutting open the used oil filter to see if there is any debree inside it is also a good idea when you are doing that oil and filter change. Then add some fresh oil and a filter and your ready to enjoy it. Best of luck on your new 223 engine!