ArthurPBloom,
No, I am not familiar with using diodes in series, but I did some experimenting and found ways to control the older station's brightness.
I connected the wiring to the constant 5 volt terminals of my 1033 transformer (in lieu of 11 volts) and the lighting was dimmer, but a bit too dim. I then connected the wiring to the variable voltage terminals of an old American Flyer Type 7 transformer that I was not using and I can control the brightness with that.
Yes, the new stations do not appear to be as dim when I turn down the brightness of the old station.
Thanks for everyone's help.