I finished my collation of Eph. 1. I used Scrivener's TR (the Greek text behind the KJV) and the UBS3. (Sorry to the purists, I can't afford UBS4.)
There are 404 Greek words in the TR. There are only 5 differences in the Greek texts where meaning is affected, and most of those are only slight differences. The main difference is that the modern Greek text omits the prepositional phrase "in Ephesus" in v. 1.
To give an idea of the differences that do not affect meaning, two of those are what are called the "moveable nu," in which the letter nu is added to the end of a word, changing neither the grammar or the meaning.
So, the differences in Ephesians 1 between the TR and the modern Greek text amount to 5/404, or a 1.2% difference.
Caveat: The Greek text of Ephesians is fairly stable, as is also most of the NT; there would be more differences in the Greek texts of Acts and Revelation than we found in Eph.
(And yes, I'm prejudiced against the UBS Greek NT.
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