And the car drives, fairly well actually. In the end I used TCK's method (cheers Pete)that he uses on his bikes. Tried going forward and hitting the brakes but it didn't budge, although it may have done had I persevered.
So I jacked the back up, started it in second, revved it, and pulled the handbrake on. Small clunk and the wheels had stopped.
It's all working fine now except the brakes, but as they're a technical issue I'll ask about them in the technical forum, as that is technically where I should post it.
Cheers!