[blucar]

The addition of a rumble seat in lieu of a trunk in a coupe and/or open car was problematic at it's best because the lower water drain channel has to be removed from the body in order to allow clearance for the deck lid to open.
I have a 36 Ford coupe that I have owned since 1952, for years I thought it would be nice to have the added passenger space that a rumble seat would provide. The Delux coupes all came with a back window that rolled down and the deck lid is the same regular coupe or rumble seat. In 1962 I came upon a coupe body that still had the complete rumble seat assembly in the car. I harvest all of the parts with the thought that I would install the rumble in my car.
Many times I started to modify my body to accommodate the rumble, when it came down to cutting the lower drain channel off of the body I would pause, to think the whole thing over. For over 25 years I paused many times, could not bring myself to cut the body.
Many people in the EFV8 group knew I had the rumble and wanted to buy it, I finally said, what the hell, sell it,which I did for a very healthy price.
Ford like many other manufactures never really addressed the problem of keeping water out of the trunk area, after all it was just a car, not a work of art until the buying public made it into one.
I find it to be very interesting that the Ford open cars of the 1930's were mostly Briggs bodied, the '39 Ford convertibles were the last to have the rumble seat option.
I have a '39 Plymouth convertible coupe, it is a Briggs Body, the last body to have have a rumble seat in the entire Chrysler line.
When I was restoring my '39 Plym conv I found that parts for the convertible were very hard to find, with my knowledge of Early Fords I found that the majority of the convertible parts, Ford/Plymouth were the same. Window channels, weather and rumble seals, with the exception of the lower deck lid seal, Ford did not have one where-as the Plymouth did have one. The Plymouth had a large hose that attached to the lower portion of the deck lid drain channel on both sides, extending down to a large hole in the tail pan. The Plymouth also had a metal L channell attached to the floor under the seat to direct any water away from the floor pan an into the rear tail pan and out of the body.
I guess that the Ford body was built to a budget, where-as the Plymouth body was built to a design. The Plymouth also had hydraulic brakes, independent front suspension, column shift and a power top, the first in the industry.