Answer:
Once you open the Remora Administrative Portal and select Edit Vehicles under the Inventory Mods tab (recall how to access edit vehicles), click on the green EDIT button (pictured below) to the far right of the corresponding row.
This will take you to the Edit Vehicle screen (previewed below) with all of the related fields you can modify.
Next, click on the checkbox next to Remove (illustrated below).
Then, you must click on the green SAVE CHANGES box (illustrated below) that appears near the top of the page.
Please Note: If you do not remove the vehicle from your inventory management tool, it will appear again on the site by the next feed we receive, unless you lock the vehicle.