Okay, by "radical Pharisee" do you mean going against the standard teachings of the Jewish religious leaders of the day? Cuz that seems pretty accurate, from the Gospels.
However... I thought Paul was a Gentile? And I thought the religious leadership, such as the Pharisees, was limited to Jews? (One of Paul's main premises in his writings was that Jesus Christ had come for both Jews and Gentiles... and all that circumcision conflict and whatnot)
Also... I'm really bummed if you're saying that the Gospels were written after the Epistles. Because I'd much rather the Gospels had been written as (or close to when) the events were happening, not 70 years later relying on memory.
Paul (nee Saul of Tarsus) was Jewish. He was, however, responsible for expanding the early Christian church to include Gentiles.
The Pharisees in this context were the more liberal of the two major rabbinic parties (the Sadducees being the more conservative).
Authorship and dating for the various New Testament writings have been the subject of some pretty heavy duty scholarship. Here's a catholic source with probably overly exact dates.