Jerry,. WOW!!!!!
That is beautiful work.
When I do these conversions I don't use a diode, I use a full wave rectifier, it's very small also less than 1/4 the size of the converter and rated at 1 amp, plenty for the strip of LEDs , the rectifier will allow you to reverse the polarity with no loss of the lighting. The strips are made for 12 v DC and with the converter you can adjust them for the brightness you desire they, the strips, also come in a variety of colors.
Ray