yes, possible the PO decided to "fix" the leaks the easy way
could be a number of different problems there, from a partly clogged rad to overfilling [seems most folks do that]
using a properly functioning thermostat will set the minimum temp the engine will run, keeping it up to the best temp for economical long life - 283's like to run 180-200, which will generate enough pressure to need a 7# cap, if your cooling system can't stand that, fix it right
Bill
