Is this a relay mod?

Disagree. Mopar headlight wiring is a bit on the small side. These cars can benefit from headlight relays. Maybe you can get by with LED, but 40-50 year old switches and connections are not doing a person any good, either.
The Wagner headlights are plug & play...wired for polarity & less current flow. Research LED & the technology. Anyway just my 2 bits..