Cheers. I went out on Friday night to give it a try...but:
  • Before I went out, I gave things a try - Idiot....the mirror is always reset by the winding action, not the photo taking, so when the bulb is released all you get is the click....face palm...
  • It was too windy when I got to my location (about 50 metres walk) there was no point.

As mentioned elsewhere, I have plans to make an electronic remote release....but I have spent a bit too much over the last month or so.

Cheers for everyones advice!