They have coolant plumbed to them. Youíll need to have a bucket ready to catch what comes out. If you are deleting them totally youíll want to remove the hoses that supply them as well and make sure you at least shunt the fluid by joining the hoses into a loop so you donít pump out coolant when you start it.
You can either cut the hoses with a utility knife or loosen the hose clamps and wiggle the hoses free. Donít be surprised if they donít really want to slide off even if the clamp is loosened. Using a knife is faster for sure.