Gary's description is just like mine was. I am still using the original 1959
LP reefer, but serious scorching in the wall made me create a new exhaust system!
For intake, I installed some aluminum vents in the low exterior access door behind refer. For exhaust, I put similar venting in wall behind & just above reefer, am still working on interior cover for it. Had to get a vent cover fabricated for outside exhaust to keep rain out, so I copied the style of my original stove vent cover on other side of trailer.
Will try to post some pics soon.