I have removed the Norcold from my MH. The screws at the top on mine were not a problem to remove. Just slit the wire under the reefer "dome" on the roof so you can lace it back together with some SS wire.
The reefer is "glued" down using something that appeared to be a black silicone based adhesive. I used an old hand saw and forced the blade under the reefer to cut the adhesive. Do that and then try to tilt the reefer. It's not easy! But, it is doable.
'02 Ultimate Advantage 40J Spartan MM - Cummins ISC
2013 Jeep Rubicon JK Unlimited