I had a misadventure with a MTH 381E, too. Contacts inside were bent and not making electrical contact. Long story short, I did not enjoy the experience of taking it apart, bending the contacts back, reassembling, testing and repeating as necessary. Like you, my OCD kicks in when I see a real or perceived scratch or blemish of what might have been a result of my surgery.
I love working on trains and love enameled tinplate but I sure don't like chips or scratches that could have been avoided. The 381E was the only train I sold because it gave me a bad memory when looking at it.