Assuming the Carrera didn't have the fillet brazing someone has gone to a lot of work, to then respray in the original Carrera colour scheme and apply Overbury's decals.
Is it possible that Overbury's and Carrera were built in the same factory at this time (bearing in mind this is late nineties and past Overbury's 'best')?
(I know sod all about Overbury's, or Carrera for that matter - am just intrigued by this)