CNELK is fast, takes me a bit longer so I would say don’t worry about how long it might take.
Also a fan of the gutless method, but I’ll gut an elk under some conditions.
First thing I do if there is any chance he can roll or slide is secure with a rope or build a rock nest.
I carry about 200 ft. Of 550 cord.
figure out where you are going to put the 1/4s before you have a 60 or 80 pound chunk in your hands.
I carried those little block and tackle kits as a kid, haven’t bothered in 30 or 40 years, but I do make use of my 550 cord to hold legs back out of my way kind of thing.
Its challenging, the ground can complicate things, but it’s not rocket surgery, take your time, stretch from time to time and you’ll get it done.