I've got two 6 year old Siamese cats who've been house cats all their life. Just moved house and they are obviously keen to venture into the outside world. Basically I'm really worried about letting them out - we are on a road (not a busy one and the garden is huge so I'm hoping there's enough to keep them occupied in their own space). Any tips? I have an old dog kennel which I could convert to acclimatise them.