I recently made a 40k mechanicus reskin mod and ive been trying to add new vehicles no no avail. I inspected your code and now my brain is jelly.

Making a vehicle is quite easy.
First you need to determine the number of directions you want your vehicle to be able to look at. The vanilla vehicles use 64, I used 128 to make it look more smooth. Then you render the vehicle in all of those directions and pack it into a spritesheet the game can use.
Create the vehicle entity with all of its parameters, make the item, the recipe and assign it to a technology and boom you done.

If you got any specific questions you can add me on Steam and I will send you my Discord tag.

Thanks for the advice my man, ill make sure to contact you if i blunder into any issues.