You may want to go ahead and have it pressure tested for leaks while you're at it (depending on how much that costs- don't know).
If you are sure that it is your radiator leaking, then you've probably found the problem. Usually when a radiator leak, it has more problems than just a hole--usu rusted, etc.
Can you actually tell your coolant level decreasing for sure. Could be coming from the hoses, you got good hoses. A good time to check for radiator/hose leaks is as car is sitting in park after driving around for a while. Even better, after you've driven around for a while, pull your hood, go back and turn off the car and then quickly go back to front and check for high pressure leaks (there is usu a surge of pressure in cooling system directly after you turn off car).
And just a thought, make sure your temperature sending unit is in goood shape. Lots of times it's the sending unit that's the problem and not actually anything wrong with the rest of cooling system.
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351W-powered 1979 Ford Mustang notchback
Stock 5.8L under 4" cowl, C4 w/ shift kit
Holley 750 cfm, Edelbrock Performer RPM intake
1 5/8" MAC shorty headers, Al driveshaft
2.5" Off road H-pipe, 2-chamber Flowmasters
Front: 225/60/15, Rear: 255/60/15 Eagle GT II
Weld wheels (15x6;15x8), 8.8" Rear w/ 3.55s
14 x 4” K&N air filter (getting the Xtreme setup someday)
"Red, thou art my companion. Hasten now your quickened metamorphosis to Green that I may conquer all who dare abide there beside me. May they be left thither behind burnt black." ---Fox Body