Gary,
If you get in contact with Gordon he should be able to let you in or organise someone who will let you into the yard. There are external power points for work and video cameras for surveillance overnight, so should be pretty safe there. If you are really lucky Gordon will hang around chewing your ear off as he drinks and watches you work. He is an old hand at watching others work now.
His place is also a short walk away if you need tools or a bench.