There is but one dispensation, one Gospel. Unless I begin with the presumption, I cannot, even by stretching the imagination, see where the belief that St. Paul was called exclusively to give a different Gospel to the Gentiles than was given to the Jews, or that he was given that job exclusively.
"There is one body and one Spirit, just as you were called to the one hope of your calling, one Lord, one faith, one baptism, one God and Father of all, who is above all and through all and in all." - Ephesians 4:4-5
Peace be with you
If God distinguishes between these gospels they CANNOT be exactly the same. Otherwise, why distinguish? And why did God accept Abel's offering, yet deny Cain's? Why, when God told Noah to build an ark, did Noah not just bring an animal sacrifice, like Abel did? Why, when Abraham was told to sacrifice his son, did he not just say "I'd rather believe that Christ died for my sins, was buried, and rose again the third day..." ?? Ya' gotta' THINK about these things, Natural. Different dispensations, different gospels. Listed by the Holy Spirit, for your reading pleasure, and your learning.