I want to know the answer to the following question:
Which style guide recommends using Vergilius to avoid confusion with Virgilius Maro Grammaticus?
All the background I'm provided with is that "Modern usage permits both, though the Oxford guide to style recommends Vergilius to avoid confusion with the 8th-century grammarian Virgilius Maro Grammaticus.". Is that enough to answer the question?
Answer: yes