Dry Weight refers to the base model of your trailer without options. It may need a better-than-average manual to separate base model from options. My Argosy manual gives weights for a surprising number of options; eg, air conditioner, spare tire, step options. Dry weight also means there is no LP or water in tanks. Electrons in the battery don't count against you (sorry, devil made me do that).
Weight without interior? If you mean without installed cabinetry, I am sure there is no published number on that! If you want an exact number at any point then you'd better find a truck stop with scales (www.catscale.com)
. Pointers are available in threads (try Search function on "CAT scale") -- techique on when you go there, try to go when not so busy with semi-trucks, etc.