There is no historical/Biblical evidence for the "Bible only" principle.
"However, it is the ultimate rule of our faith."
Same answer as above.
Allow me to suggest you read any of the ante-nicean fathers. They cite it as an authority continually.
And, to quote Paul, “”All scripture is inspired by God and is useful for teaching, for refutation, for correction, and for training in righteousness, so that one who belongs to God may be competent, equipped for every good work.”
So, “The Bible Only” as being DIRECTLY from God is a matter that is settled by Paul.