Peter didn't eat anything unclean, but that is semantics at this point.
anyway, Paul was part of the Sanhedrin, he was Jewish, but he was also a Roman citizen that is why he was able to spread the word more easily to the gentiles. the main point of contention was that the Apostles were worried that he was a spy, seeing that as Saul, he was persecuting any and all Christians he found. The main issues that he, and Peter to a lesser degree, were trying to point out was that the legalism that was rampant in Judaism, was NOT the way to Christ and you didn't have to adhere to the old sacrificial customs, because Christ was the Ultimate sacrifice and it was no longer needed.
and as far as not knowing Jesus personally has no bearing on whither or not his believes or his teachings were an extension of Christ's teachings. Heck neither Luke nor Mark were of the 12 and they both wrote 2 of the Gospels and Luke wrote Acts.