Ahhh, yes, this could be a VERY interesting thread! But I too, cannot pass up on the opportunity to contribute.....
As someone from another Commonwealth country who has been on both sides of the fence (private collector/restorer and govt museum curator), there are a LOT more issues to consider in the museum sphere than with one's own items. In simple terms, it is not the look of the item that is the deciding factor in considering working on a item (be that to acquire, to restore, to simply conserve as is, etc etc), but a myriad of intersection considerations, many of which often conflict. Did the PzKw2 arrive at CWM with the incorrect light? Who/what/when/where were they acquired/put on, etc etc. It's not only the battle history of an object that is important, but at the end of the day, the curatorial staff and conservation staff make informed and balanced judgements based on their experience and recommendations to management about how management's goals for the museum collection (ie how this items fits with the overall policy) can be achieved with a certain item. Again, this can range from 'conserve it as is', to full restoration to running standard. The question is never as simplistic as 'its got the the wrong lights...'.
On the other side of the coin, as a visitor to CWM many years ago, I have to say I was a little taken aback with the many minor factual technical errors in the displays, but every museum suffers from that to a greater or lesser degree: the AWM certainly is guilty of that, too. It's how they react and respond when informed (politely) that counts.
Mike C
(retired Head of Military Heraldry and Technology, Australian War Memorial, Canberra)