Managing attribute information to provide output for other applications (e.g., applications for generating manufacturing instructions) may involve identifying attribute information associated with instances of a selected item type (e.g., parts fasteners). For example, in the case of fasteners, each of the instances of the selected item type is associated with a common part or product. The instances of the selected item type may then be sorted into initial groups based on grouping criteria such as part ID number, etc. Proximity rules may then be applied to the sorted instances. Applying proximity rules to the sorted instances may include grouping the instances into groups depending on whether or not have common relationships with other items. For example, in the case of fasteners, the proximity rules may involve determining whether each fastener passes through the same set of solids and/or shares common attributes.