Hi Phill
I would go with rjwoods advice in the not pushing it about or playing with it the only part on mine that moves it the front steering so i can turn them to fit a diorama but the wheels them self they do not turn no need for it after all its a model to look at and be proud of.
As for your halftrack it looks great if you need any help just let me know only too pleased to help out.
Robert.
http://www.scale-models.co.uk/showthread.php?p=34134 more pics over here......