Tom. The extensions are parallel to the ground, are in two pieces and the bumper hole is 8" from the end of the frame. These are bolted on, not riveted.
Jim, I am working on a Plymouth convertible coupe and the dust pan over the gas tank is the same as a Dodge coupe, convertible or other coupes. I plan on cutting holes in a spare pan and welding up the spare tire holes.
Also. Does your Brougham have "Two door Sedan" doors? Just curious if the longer wheelbase had longer front doors.