DnD Ships & Vehicles?

I am wanting to create a ship or vehicle NPC sheet. I would like to edit the roll20 sheet as a base, and add a is-veh option. This would only change the health, and AC section of the sheet to be crew and cargo capacity. However pulling the roll20 sheet from github and I get a FAR different sheet. I am pretty strong with both HTML and JS, but do not want to build a sheet from the ground up to accomplish this. I also would like minimal impact on my players. What should I do.

Sorry to double post, but a bit of an update. As you can see I have the saltmarsh stats add, I figure actions and the like should stay the same. I have not figured out how to tackle ship parts. I would like them to be added similar to how properties are added with their own template. One thing I can not figure out is how to add a flag to toggle the Vehicle stat header, and the non vehicle stats. I have added the checkbox. Here you can see I have a veh_toggle class and a attr_veh I can set as well as the checkbox, located in the NPC options... I can not figure out what to do from here. I am not strong enough with raw CSS to understand some of the realtionships, and don't know what to look for to answer the question. "How to toggle html elements via CSS styeling." I will keep digging but if someone can help with this, thank you.              < div   class = "row" >                  < input   type = "checkbox"   name = "attr_npc"   value = "1" >                  < span   data-i18n = "npc-u" > NPC </ span >              </ div >              < div   class = "row" >                  < input   type = "checkbox"   name = "attr_veh"   value = "1" >                  < span   data-i18n = "veh-u" > VEH </ span >              </ div > < div   class = "licensecontainer compendium-drop-target monsters"   data-licensedsheet = "attr_licensedsheet" >      < input   class = "npc_toggle"   name = "attr_npc"   type = "hidden"   value = "0"  />      < input   class = "veh_toggle"   name = "attr_veh"   type = "hidden"   value = "0"  />