You could be right, I'm not sure "0719" means July 19 on the early tags as it would on the later tags. I will read up on it when I'm at the office tomorrow and post '61 tag and number decode if I don't get interrupted.
225 was very-late-'61 availability on Valiants, deliberately held back to use the optional 225 to draw buyers to the more expensive new Lancer. Other clues: alternator on passenger side of engine (driver's side in '60), intake manifold made out of cast iron (aluminum in '60), black text on white background instrument cluster (white text on black background in '60), one single central dash turn signal indicator (separate left and right in '60), white dash knobs and pushbutton sleeves (black in '60), red and blue Valiant "V" logo in steering wheel centre (red-and-white crest and/or gold cursive "Valiant" script on red field in '60), ceramic ballast resistor (metal-housed resistor in '60)...