As for the blotched lettering, if its due to a Sharpie, the ink is soluable on alcohol. If you dampen a towel in alcohol and wipe it over the letters and see black on the towel its from a pen. Quick wipes with a small paint brush, Q tip or towel should reduce it, may not remove it completely if the ink has stained the paint. Don't soak it in alcohol as it will eventually soften the paint. Stop if you see yellow on your wiper and let it dry.
As for the SP cars, I think all the red brown cars have the complete circle. All the light brown cars have the broken circle. The early light brown cars have corner stirrups which were omitted the following year and there after.
BTW does anyone else have a modern TTOS repros done a few years ago? Erie, SP, and PRR.
Pete
