Set column position in Highcharts -

i'm truying build column chart 1 series overlaps other (2) series. i've attached picture better understanding.

thanks help!

something possible, take look: http://jsfiddle.net/rlskooht/

• set: grouping: false, zindex: (e.g.) 10, pointpadding: 0.3 on top series
• first series should 1 on top

code:

var chart = new highcharts.chart({     chart: {         renderto: 'container',         type: 'column'     },     xaxis: {         categories: ['cat1', 'cat2']     },     series: [{         grouping: false,         data: [70, 50],         pointpadding: 0.3,         zindex: 10     },{         data: [123, 100]             },{         data: [100, 90]             }] });