For Model A's and cars in the early 30's with spoked wheels we use a plastisol coating to seal the spoke ends and permit the use of tubeless tires. You can google "plastisol" and get information about it. Also called a "dipping" coating and is what's used for a cushioned or non-slip coating on tool handles like pliers. It's the bonded on coating and not the cheap glued on sponge stuff like chinese tools. Wheels must be completely clean to bare metal and just the dropped area where the spokes or rivets are is coated. Some of the old wheels bead design is not well suited to tubless tires so this needs to be checked out. When coated with plastisol the liner can be omitted if a tube is used since it isolates the tube from rivets/spokes.

Evan