Customization - Accessing a field in another table

Vantage 8.03.407

I'm trying to put a custom textbox for vendor part number on:

Production Management | Job Management | General Operations | Job Entry

Job Detail Tab | Materials Tab | Detail Tab

The field I would like to access is under
Table: VendPart
Field: VenPartNum

The DataSource drop-down does not offer this field. I've played around with creating a custom "Foreign Key View" under "Data Tools", but I can't find any reference to VenPartNum. Perhaps I'm entirely misunderstanding the concept here, but I don't think I can use this option.

I read a couple of other posts saying that I may need to create "list lookup", but these suggestions are accompanied with an example.

Can anyone help me in creating a "Foreign Key View" that works or an example of a "list lookup"?