Mercedes sprinter passenger seat removal

I have a 2002 mercedes sprinter 311 van with a double passenger seat. I wish to tip or remove the seat so I can access the space beneath it where there appears to be a fair amount of electrical equipment. I have removed a hex head bolt from each side near the rear of the seat cushion but cannot tilt or move the seat. has anyone knowledge of how to remove this seat please?. the handbook has details for a single passenger seat but no info on the double. many thanks Peter