Joined: Jan 2008
Posts: 23,639
Likes: 1,106
From: Mans of NC & SW UT Desert
Bikes: 86 Katakura Silk, 87 Prologue X2, 88 Cimarron LE, 1975 Sekai 4000 Professional, 73 Paramount, plus more
I would keep the Centurion, as based on your pictures, it is the bike that fits. If you like the drivetrain on the Trek the best (I do not blame you, it would be my favorite), I would just swap wheels, derailleurs and shifters between both bikes.
I have a very similar composite Carbon bike hanging in my workshop (a Giant). I don't ride it at all. I ride my 1987 Schwinn Prologue instead, with a modern drivetrain I installed.