Welcome to Expanded Interiors for Rodina. This is a MODDERS RESOURCE and is FREE TO USE/ALTERfor your own mod if need be, however a small shout-out would be splendid. This resource expands the limits to the size of the ship interior from 24 x 42 to 48 x 42. This now allows you to shape an interior to the shape of your ship if it is wider than the vanilla limitations.
How to use:
1. Load in the "ExpandedInterior-Open" in the Interior editor menu. This interior is meant to 
be way too large for your ship. This oversized interior is meant show where the limits/boundaries are 
with your interior. Go and remove parts of the interior that exceed your ship's design.
2. Then save this layout as whatever you wish (i.e: "Boundaries")
3. Go to the UserData folder
4. Open the inteior in Notepad (however Notepad++ is best)
5. Now you should see a map of the interior that is compromised of o . X
o : Bridge 
. : editable space
X : uneditable space
Whatever is the open area is the o (assuming you used the bridge tileset), the area outside of
this should be turned into X as to make it uneditable in the menu.
Note: The bottom two rows should be left as is to avoid complications with the airlock.
6. Save the file
7. Load the file into Rodina
Now you should have a template for you custom ship shape, enjoy!

Thanks to Raptormeat for aiding me so much with this, and for essentially writing the code for the interior file!