Multiple Material Subelements

Hi,

I am trying to determine how to charge purchased items go to different material subelements.

I have two material sub-elements defined:  Material & Equipment.

The organization uses Average Costing, and the average cost type is not directly updatable in the Item Costs form.

The Default Material Sub-Element for the Oranazation is set to Material, and all transactions are defaulting to Material.  I need some items to be charged to Equipment.

Project Manufacturing is enable for the organization, and we need to map expenditure types to different material subelements.

Not sure how to associate material subelement to items for average cost organization.