might sound crazy. but i would look into a Giant tuna bag. take your time and get him into the bag while your both in the pool. my biggest fear moving a pima that big would be him thrashing and falling. even then youll want 2-3 people and anything can happen. the bag is dark and will make the fish a bit calmer and he will remain wet while being moved and if the unthinkable happends and he gets dropped. the bag provides quite a bit of protection. as mentioned above. its not to bad doing the actual trip once in his moving container. its the process of getting him out of his pond and into that container that is 90% of the stress.
Definitely a great idea. I have actually made a net/sock for him. Its just made from the hoop of an old net and just sewn fabric about 8 ft long. Looks like a giant pillow case attached to a hoop. Hopfully it will be durable enough for the pima, they are so dang strong.