It is a good ten years since I did this for a friend who had a repainted, flush glazed, highly detailed old Mainline model. My recollection is that it was very straightforward, but having done several of these sorts of things, without the item in front of me it is hard to remember.
Bear in mind that there have been two Bachmann versions of the 45. If you go for the earlier model it will have to be a s/h purchase, (31-077 or 078 are two of the relevant product numbers) : this model has the Mainline body shell tooling, with a Bachmann designed centre motor chassis, which is a good mechanism, if not as refined as the current version. This model still has the buffers incorrectly body mounted. If you buy a current version, for which Bach have made a completely new bodyshell and significantly revised the chassis, the fit may not be so simple, and the bufferbeam is now correctly on the bogie frames.
Bear in mind that there have been two Bachmann versions of the 45. If you go for the earlier model it will have to be a s/h purchase, (31-077 or 078 are two of the relevant product numbers) : this model has the Mainline body shell tooling, with a Bachmann designed centre motor chassis, which is a good mechanism, if not as refined as the current version. This model still has the buffers incorrectly body mounted. If you buy a current version, for which Bach have made a completely new bodyshell and significantly revised the chassis, the fit may not be so simple, and the bufferbeam is now correctly on the bogie frames.
