VENDOR_ADD_DATA for custom LFM2 fields

I am looking for a way to use the Vendor Maintenance Program SAPMF02K (XK01/XK02/XK03) to update custom LFM2 fields.

Since there are multiple LFM2 plant(WERKS) Records for a Vendor/Purchasing Org, How can the screen be configured to narrow in on the desired LFM2 record to update?

Goal-Have the additional field appear on the SAPMF02K vendor plant purchasing data screen (330) or as separate button on the alternative data plant screen (341).

Presently I can prompt for the plant and update the existing record, however this is not useful in view mode as the plant field is read only. It also does not look/feel like SAP's XK0x transactions.

Following SAP Note 580266 I was able to use VENDOR_ADD_DATA and VENDOR_ADD_DATA_CS use the custom screen.