Hi
looking at the new model 41291 they have the chimney wrong for this loco.
The locos up to 41289 had the squat LMS cimney, 41290-41299 the taller thinner/slightly tapered chimney and 41320-41329 had the taller larger diameter one (like the earlier one but stretched). Some earlier locos were retrofitted with the later 3rd type. This all came about to draughting tests done at Swindon on an Ivatt 2-6-0, where a longer chimney was found to improve performance. It is written that when the loco returned from Swindon to Derby the chimney by then was a hideous shape, due to the test mods, where at Derby the external shape was made more pleasing, aesthetically. As an aside, the locos from 41290 also had the round eave cab profile and the later pattern pony truck with integral guard irons.
Also if you look at the photo they have on there website they are still showing the new model on the old chaise,confusing the issue. I did send this info to Bachmann when they announced this loco pointing the chimney out.
Darren