Sorry, I thought I had answered this late last night.
I am sure you can work out something.
Here is a picture of a door and fish.
You can see there is room above the fish. The problem would be how to hang it. You could use a 3M command hanger but would need to worry someone might walk off with your FE. We bring wire ties. Here is info on that:
Whats With This Zip Tie Business
A zip tie (or cable tie) is a handy piece of equipment to secure your fish extender. We dont want any fish extender nappings. Lets face it, even on a
Disney Cruise; there are people out there that have deviousness running in their veins. The zip tie helps to deter this. This is an explanation from a fellow DISer:
If you look at the ribbon on any fish extender (that is what you place over the fish) that is how the "extender" hangs on the fish. It is very easy to just remove the extender by just un-hooking it from the fish. So, you take your zip tie and cinch it around both of the ribbons that are hanging from the fish on both sides... and you cinch the zip tie so that the two ribbons squeeze around the fish making it impossible to remove the extender.
The zip-tie goes around the ribbon or string that attaches to the fish... and you place it just under the fish... it actually scoots itself up to the fish as you tighten it... the trick is to leave it NOT so tight so that you can get your scissors or nail clippers thru it when you are ready to take it down.
Think about it like a Club except instead of securing your cars steering wheel, it holds the strap your fish extender hangs from securely to the fish.
The door might be an option but again, how do you hang the FE and do you want to cover the room number block? Or do you want to use the bock for other decorations?
such as the Stitch ears or Minnie Pirate
or maybe Sailor Donald
Here is a link to the patterns for making these and other magnets.
http://www.disboards.com/showthread.php?t=2172891