Henry applied for and was granted US Patent 2269451 A

This is an excerpt, including the spelling!

Provide an automobile body construction of improved’ construction. 1 v

More specifically, the object of my invention is to provide a body construction in which plastic body panels-are employed, .not only for the doors and side panels, but also for the roof, hood and all other ‘exposed panels on the body.

Plastic parts have many advantages in that they produce a quiet body, may be molded to exact sizes, may be formed economically from soy bean oil, may be readily replaced in case of accident, and result in a lighter construction.

However, there are also many disadvantages to g all such constructions in the past because the panels are not able structurally to resist the stresses to which such panels are exposed in the conventional body. In the present all-steel body the “panels are depended upon almost entirely to resist the many stresses set up in the body.

An object of this invention is, therefore, to

provide a body frame structure which will resist all normally encountered stresses independently of the body panels.

The full patent detail can be found here

It’s believed the war overtook things and the idea was never pursued.

There is also an interesting article on Henry’s plastic car by Ben Judge that can be found  here at Money Week