How do I view a numeric reference field as a text field on forms?

No problem, proxy fields to the rescue.

In many cases when you make a relationship the key field on the parent side is a record ID which is not meaningful to any users. So what you do is you look at the field properties for that field and select one of the look up fields on the right side of the relationship as a proxy for related parent.
What that means is that a proxy field will behave as a parent name for example if that is what you chose to represent it or in your case funding agency name, but only in edit mode on forms will it suddenly behave differently and will act as related parent.

So all you need to do is to set a proxy field for related funding agency and then on your form you would list the proxy field which is probably something like funding agency name on the form. You do not put related agency on the form.