Yea drive it up on some timbers. You dont really need to get underneath, but its easier to actually see the 3 bolts.
When i got the front up i had to use wood, a low level scissor jack and a normal jack and that lifted the back up aswell I recon my drive will be fine to do the bumper as its not totally level and will allow one side of the rear bumper to be higher and enough for me to look underneath May as well take it off one day mate, sounds really easy tbh!
Trust me the rear bumper is easy to remove.