How hard to add an outside storage door?

[GMcKenzie]

I have a big chunk of unused space at the back of my unit and would like to add an outside door. I can get access to the inside by pulling out the kitchen drawers and have easy access outside. Is this tough to do or is it as simple as it seems?

Get a door.
Measure twice.
Cut with a dremel or similar.
Frame the inside with 1X1.
Add the sealant.
Attach the door.

Am I missing anything?

[BirchyBoy]

Is the floor in that area strong enough to support anything?

[GMcKenzie]

Don't see why it wouldn't be. It's just part of the kitchen. It supports the pantry a foot from where I want to add the door.