Firefly simulation

We are developing a firefly design based dron in our non profit organization NIC, nepal for supply of medicin in rural places mainly targeted for delivery during emergency period like earthquack. Begine a person working in the software part, i am trying to do SITL and HITL simulation in gazebo with firefly6 model. But as i cloned the Firmware repository, i didn’t find the firefly6 urdf/xacro/sdf model nor i find the airframe for HDL/SDL simulation.
I’m a beginner in px4 and this dron things. Should i develop seperate xacro model for the firefly6 robot . And how should i simulate this in simulation as i saw their is no fierfly6 SIL/HIL setup in qgroundcontrol setup.

I think you can write a new sdf file based on firefly6. As far as i know, only sdf is supported for pixhawk gazebo plugins. If you want to use rviz, you have to write the urdf version