You have a beautiful camper. Trying to be helpful, the model number you listed as T278SR does not match your floor plan or any other 2007 model Sunline. I know these numbers can easily get mixed up.
Your pictures show what Sunline called a 2007 T286SR. It has a front kitchen, the front left side slide has the dinette, couch. It has a pass through mid camper bathroom and a rear queen sized bed room.
The floor plan matches this diagram. Please confirm this floor plan matches your camper.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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