roof insert - 33 Tudor

[Doctor's Ford]

My 33 Tudor restoration continues and found the following issue shown in the photo: After removing the old paint from the top of the body I can see a line of welding of a lar metal roof insert overlying the area where I see rubber insert on other cars. My car had no vinyl or other type of material on top of the roof when I purchased it and I was told there was no modifications on the car. Can somebody help with the following questions?
1) How is the original roof of 33 Tudors like?
2) The rubber/vynil piece that is seen in many cars is just attached to the metal surface? or is part of a larger insert structure
3) What do I need to do to stay original?

Found this kit on Lebaron Bonney company: "Kits include top material, cotton wadding, muslin lining, insulating strips, and instructions. Tacks are included where necessary" but don´t know if it applies to a car that is all metal on the roof and does not need insulation.

Ideas and comments always appreciated. Thanks to all. Manuel