How do I change the body type in a custom config?

In Blender, I have made a open top version of the Sunburst, I have an info.json thing up and I can see it in the vehicle selector. Because I am new to mod creation, I edited the Sunburst's CVT Stock json file to fit my thing. I have the .dae file of the open top, and the jbeam of am hard top (I will work on this later.) How do I change the body from the regular hard top to the open top?

 

I think what you want is selecting the open top body in the parts selector, right? If so, you should have a jbeam file, because only the jbeams can make a part selectable in the parts selector. If i'm wrong, please make your question more clear

 

Do you want to see your car with a standard sunburst list?
Or do you want it as a separate car?

 

Standard. @S.Ali.M suggested something, I am going to do it.
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Yes. That is what I am doing. I am nearly done with the opne top jbeam, and I'll see if it works.