Adding Ubercart Product Kit Field to Exsiting Field Group via 'field_group_build_pre_render_alter'

I am using Ubercart with the product kit module. The problem is that the product count is added by the module during node creation so I can't add this field to the field group in the manage display pane. How can I add this field to the field group just before node is viewed?

- The field I need added is 'products'
- The parent tab group is 'group_tab_group_pk'
- Has two children tabs that are 'group_more_info_pk' and 'group_specifications_pk'
- I would like the 'products' field added to 'group_specifications_pk'
- 'group_specifications_pk' has two existing fields of 'weight' and 'dimension'

bundle = product_kit
node = full

Example of product field output:
8 × 90 Bracket
15 × 120 Bracket
26 × I Bracket
26 × T Bracket

Thank you for your time. I have search everywhere but can't find an example that's close or complete.