Re: DL&LW ARA boxcar
Larry, love the show . . .;^)
Whether or not you use K or AB depends more on the date you're modeling than it does on the slogan.
AB brakes were first introduced in 1932, and became required in, I think, the late 40's. I seldom
can remember that second date. I suppose you might be in a time slot of the late 30's/early 40's
and be able to have a slogan if it was in place then, and a K brake, but it's a tighter slot then.