I have a Fiat ducato, My son had a Fiat Doblo. I plylined both. I did not use a kit. I used a tape measure and I cut templates out of paper then transfered it onto a sheet of ply.
The ducato van down the right side as some three by two behind the plylining si I could screw brackets on too carry extra poles.
I insulated behind the plylineing on the ducato but was not able to on the doblo.
Painted Gloss white to ply to make it look nicer. Both floors proteckakoted. No ply on floors. Heres the pics. gives you an idea.
Nel