How to modify Default Cubes in AX 2012

Dear Friends,

Good day.

I have deployed the default cubes in AX2012 server. In RetailChanneltable already InventLocation field is there. I want to show this field in Excel Pivot field name selection box.

From the above link i have tried upto this point (Open the Analysis Services project that contains the Retail cube in BIDS. In Solution Explorer, expand the Cubes node and then double-click retailCube.cube). Then after i am not able to understand the remaining point.

Can any one please guid me step by step process to achieve my requirement.

I really appreciate your reply.

Thanks and regards,

Abbas. I