Im trying to figure out how to have 2 product codes in my store. We sell car parts and in our old store we were able to list
Manufacture Parts Number:
Our Part Number:
This helps us a lot because it will allow the customer to see the original manufactures part number and not only ours.
SKU's are for you unless provided|mandated by vendor|supplier
For any similar data with singular items put it in either a product tag, or product metafield, or product title or product description
For variants put it either in a metafield ,or make it one of the variant options so it shows up pretty much everywhere