I just replaced the pigtails in my gas cabinet as they were coming up to 5 years old. That's a sod of a job with 2 x 13kg Propane cylinders to heft around; and remembering that the threads are the other way around to normal; and the bit of carpet in there to stop noises, getting caught on the safety lip that the cylinders sit on; and having bugger all room to work with the cylinder spanner!
Most of all though it was a sod when I caught my little finger between a cylinder and the floor which took all the skin off.
Its surprising how far a swear word carries in a small, quiet village!