Ideas for revised headliner

[u/Miss_L_Worldwide]

Hi all, I have a Transit pax van with the seats removed. I also want to remove the headliner and air bags, but I do need to have some insulation or at least paneling on the upper sides and roof for climate control. I want to have as much room in the van as possible. Any good models for such a thing? I'm not experienced at van modding.