Every woman I ever dated had a tribble of some sort, that they were very attached too.
There are two ways to make the construction more stable: Either add some triangular supports to the bottom of the step to prevent it from sagging or cut a hole into the fuselage, push the step through it and glue it to the back side like I did with the opening tab of the Aurora hatch:I attached the door step using the original card flap and gluing it to the outside hull skin. This works OK, but I wish I’d been smart enough to come up with something better.