I just purchased a 1930 Model A and the soft top i
It depends on what type of material your top is made out of. If it is the naugahyde type of material with a cobra or colonial grain, Armor-All seems to work best for preserving and protecting the top. If you have a fabric style top made out of something like Hartz cloth (which is like a canvas), I would suggest you check with a company like LeBaron Bonney that specializes in that area. My first thoughts are Scotch Guard, but check with them to be safe. Their phone number is 978-388-3811. They may even sell something for that purpose.