Is there a method to mass upload Payable pay group lookup values?

Summary:

I need to upload 6000+ pay groups to be used at invoice installment level

Content (required):

I cannot find standard way to upload payables pay group lookup values, client need to be able to select contract specific value at payment level and the only field avalilable at payment is the pay group. best option we found is then to move contract flexfield to invoice installment through PAAS enhancemnet, but we fist need to create these values in the payable pay group lookup list

only OLD(2015) reference found is What are the Options Available to Upload Pay Groups In Fusion Payables (