What do you mean by Supplier part numbers? is it the sequence number of the supplier Id?

no, it's the field on the ITMBPS table to store the product number that the supplier references the X3 product number.

Why not just extend ITMREFBPS from 20 to whatever you want in the table dictionary? ITMREFBPS appears in a myriad of screens and windows, so those would all have to be re-validated. (I'm not sure the best way to go about that; as ITMREFBPS is just an A type. I guess you could dictionary validate every A, but it might be faster to re-validate the screens individually. Or apply a custom activity code to that field, validate on that field, then remove it.)

I agree with your suggestion. This would be a last resort as spacing on screens, inquiries and reports may become an issue. I was hoping that someone may have handled it differently. Thanks!