The DW series used the 1737 cab ,or better known as the "fat cab", through 1959. It would have come with a 8341A 4 speed auxiliary. It was built for heavy haul from the ground up and should be left like it is because it still can be used for that. If it wasn't so far, I would buy it to use. I would add a rolling tail board. As far as using it to pull an RV, I'm sure you would want to put in a single stick transmission and go to a single drive axle with air ride. I don't know how you would insulate the cab enough to where the noise level and heat would be at an acceptable level.
