Looks like you have essentially the same as I do. My dump bed is from Daybrook in Bowling Green, OH.
My truck is currently sitting in south MS and I am about ready to try figuring out how to get it closer to me so I can do some restoration on it.
It has been such a blast to operate that old EC-302 during "Cruisin' the Coast" in South MS, but since I am not living there now, I need to get that pile of rust up here to make it pretty - and more functional.
It really tripped folks out to see me hand-crank start that old thing!