Rossored - right click the chart, select Chart Settings, and change the start and end time of the chart to day session hours. If you still want to see the overnight data, open a second chart for the same symbol but set for 24 hours.
Oatman, hi lo etc is already displayed at the top of the Sierra screen under the menu. You can also right click the chart and select "Chart Values" to give you a crosshairs which makes it easier to see the bar you are viewing figures for. Not only that, but you can also select "Values Window" from the same right click menu (or press F3) and get a seperate window with hi low open close, and all the figures for all your studies too.
HTH,
H.