Handling of Opacity option in InteractiveTradingChart

In this code how do I affect only blue line with Opacity and Thickness but not the main financial plot?

InteractiveTradingChart[{"MSFT", {{2008, 10, 1}, {2009, 3, 31}}}, {"ExponentialMovingAverage"}, BaseStyle -> {Thickness[.07], Opacity[.3]}]

Try the LineStyle style option:

InteractiveTradingChart[{"MSFT", {{2008, 10, 1}, {2009, 3,     31}}},
    {FinancialIndicator["ExponentialMovingAverage",  
    "LineStyle" ->     Directive[ColorData[1][1], Thickness[.07], Opacity[.3]]]}]