This week, WTWF takes a look at the members of the Jimmy/Joe version of Wings, which lasted from the recording of Paul's brother's "McGear" album through the recording of "London Town".         Where did the individual players come from?  Did Geoff Britton's references to karate facilitate his exit from the band after only five months?       What about those guys in the horn section?     All this and more in Part One of our look at the longest-lasting iteration of Wings.