check out the "Reverb Adjustments" on this page. http://wald-electronics.com/preampmods.html
light up top seems to be the preference.
"Tone is in the instruments. Technique in the hands. Do what you will." ~quote from some guy at the TGP forum
"Without a doubt, the quality of your instrument will effect your tone, and any pickups, effects, amps, and microphones used along the way will also have an impact on the sound waves."~Cameron Mizell