TeeAnn, I don’t have dimensions but will share the little I know.
There are two sizes overhead (over the cab) beds depending on front cap. The RV is 90 inches wide, so bed is plenty long when sleeping across as intended. The aerodynamic fiberglass front cap narrows as you move forward, but seems taller at rear edge of bed which makes it a bit easier to climb in and out of bed. When much younger my wife and I slept in Class C overhead bed a few times and the real issue for us (and I expect most) was for person at very front of RV climbing over the other person because there is so little headroom. It’s far worse than climbing over each other when sleeping in a corner bed (have done that too and wouldn’t want to again). One person up there isn’t too bad.
Dinettes in Cruise America motorhomes we’ve rented seem about the same size to me, and they're just wide enough for 4 thin/average adults to sit. When made into a bed, the ones we’ve rented were just under 6’ long and plenty wide for one person. We used a twin-bed memory foam pad on top and it was just the right width but a few inches too long. My wife said she slept great. The dinette is definitely too narrow for two adults in my opinion.
When we looked at the 19G, we figured she would sleep on dinette and I would take the overhead bed, or I would build a bed extension next to dinette. In the end the size didn’t offer enough space over a van camper to make it worth it for us. If a little longer, with permanent Twin/King beds and dry bath, we’d be more interested. For us the 19G is not worth it because we’d have to park it offsite while a van we can park at home, and outside storage is very limited. Great unit for the size though.