According to a few sites:
http://www.jamminsam.com/ http://precisiondrum.com/html/body_wrap.html you should take the old wrap off. Apparently, though, american made drums usually had the wrap glued all the way around the shell, as opposed to just glueing at the seams. If the rims and all the hardware fit with two layers of wrap, I'd say go for it.
Rogers were extremley well made drums, and I bet it would be an enormus pain in the buttocks to get the old wrap off.
Regarding any change in sound; I'm not sure, but an extra layer of wrap might deaden the tone a little, or maybe focus it. I really dont know, perhaps it will do nothing. Hope this helps!