Hi I am instaling the lighting for my train yard and engine house... I have 18 lights. I am using Brawa double yard lights and 6 lights in my engine service facility they are connected in series and the light seem really dim. when I have one light hooked to the power supply it is nice and bright... Maybe a little too bright... Would it make a difference if I hooked them up in parallel circuit? I don't have 18 power supplies to hook each individual light to nor would I want to... What is the trick to get the lights a little brighter?