Date registered: Aug 2009
Vehicle: '72 250C, '74 280C, '85 500SEL, '81 300CD.
Location: Tucson, Az.
Mentioned: 3 Post(s)
Quoted: 52 Post(s)
Ahhh! Part of the problem is solved. They removed the latching mechanism to install the amp. This explains the unattached vacuum line. They probably figured everyone would enter/exit the passenger side.
You can release the locking hooks using a long screwdriver to move the latches unless they did away with them. Look for a hook in the space between the pivot space between the upper and lower seat side supports. Put a little pressure to move the hook on each side while maintaining a gentle forward pressure on the seat back.
I imagine the amp is what is impeding the seat from full travel.
Gad. I hate aftermarket stereo installs.