Seem to be unable to do this , from IB faqs it says :
Attach a Trailing Stop to a Limit Order
You can attach a trailing stop order to a limit order. The attached stop order is activated when the limit order is filled. You must route attached trailing stop orders through Smart order routing.
To attach a trailing stop to a limit order
Right-click on a market data line for a limit order.
Select Attach Auto Trailing Stop.
To modify the trailing amount, use the Aux. Price field.
To modify the stop trigger method, right-click on the attached trailing stop order and select Trigger Method.
To view/modify the stop election price, display the Stop Price column from the Order Row section of the Page layout
When I click on the market data line there is no selection attach auto trailing stop . also I don't see smart order routing , there is a best routing
Attach a Trailing Stop to a Limit Order
You can attach a trailing stop order to a limit order. The attached stop order is activated when the limit order is filled. You must route attached trailing stop orders through Smart order routing.
To attach a trailing stop to a limit order
Right-click on a market data line for a limit order.
Select Attach Auto Trailing Stop.
To modify the trailing amount, use the Aux. Price field.
To modify the stop trigger method, right-click on the attached trailing stop order and select Trigger Method.
To view/modify the stop election price, display the Stop Price column from the Order Row section of the Page layout
When I click on the market data line there is no selection attach auto trailing stop . also I don't see smart order routing , there is a best routing