Cool, another Peninsula type.
You may take a look at the front sway bar. If the noise comes up every time you kill the engine, you may also want to take a look at the engine mounts and the tranny mounts.
Except for the noise appearing every time you kill the engine, it sounds a lot like a problem I had with a '65 Chevelle a while back; one of the bolts holding the front sway bar to the wheel suspension assembly had broken clean off. Combined with bad springs and bad shocks, the car handled horribly in turns...
Hope that helps a little. Good luck!