Has anyone swapped out this shell,i read on another forum that a fellow posted a review of BACHMANN'S DCC RS3 that the Atlas shell will drop on with no diffiiculty,as i don't have a bachmann rs3 at this time would there be a member whom has done this &offer comments, also as ATLAS used the same frame assy for their GP7'S&9 would these shells also fit or maybe the ATLAS GP7&9 will even fit on the new BACHMANN DCC GP7.this very important ot me as i have a lot of older dlocos in my favourite livery of CNR&CPR and this would be a very ecconomical way to up date to DCC without repainting&decaling,also as a senior with limited funds,this would be the cats meow.also SPOOKSHOW'S review of both BACHMANN locos is rated an A .Any help from members would be greatly appreciated.