Recently purchased a 1973 dart sport 340. The fender tag date code reads 930 (assuming 9/30/72). The block numbers match the VIN. The engine has a casting date that reads 1/19/71. The engine appears like its never been apart and is orange and has a orange 340 dual snorkel air breather. The heads have no letters stamped between the spark plugs. Could this be a factory 275 horsepower 1973 dart sport???