My apologies for the delay but i have word back from custom cables.
That part number can’t be modified as is, we would need to create a new part number. I have the email and questions needed to email this out and get this option assembled :
Customer number
Full contact information including name, company name, location, phone number, and email
List of components for assembly
Drawing of the assembly(customs should be able to help out with this if the customer isn’t capable of providing a drawing)
Quantity that they want to order, and if it will be a single purchase, or if it will be a quarterly or yearly purchase.
We also have a link here that shows how to if you would like to view it 
Digi-Key Value Add Capabilities > Rectangular Cable Assemblies
Hopefully this gets you all set.
Thank you
Ryan