Thanks guys.
Hmmm, I don't really feel I can say which company it was because we've used them in the past for sets and props and will be doing so in the future as well. Thats the problem though really, they've treated it as a prop - needs to be sturdy (inch thick wood for the frame!) Still, the pod 4 is lovely, nicely counterweighted so I have no trouble.
As for the pod 3, it turned out no one else could use it either, so the clever backstage people have managed to rig it up in such a way that it's just about possible for me to do it (sadly it's got a flapping head now rather than the jaw dropping, but there was really no choice) so I will just have to do my best.
Cheers,
Deb.