Need more control over populating the Next ResSchl field

Currently we control what options are available in the Next Schl field via COD table : STU.NS.

The COD : STU.NS list includes our 'traditional' schools (Not ASP, Summer, other 'paper' schools) as well as the High Schools we are feeders for.

However, the Next ResSchl seems to ONLY be populated from the LOC table... which is problematic for a few reasons:

1) The options don't match the options in Next School

2) The options don't include commonly needed values (the resident High Schools of 8th graders)

3) The options include invalid options (the ASP, Summer, and other 'paper' schools)

WE would like to have the Next ResSchl field have the option of populating from the COD table : STU.RS (which is similar to how the Next Schl field works)