Help: E30 seats

["Fadeev, Alex" <Alex.Fadeev@xxxxxxxxxxxxxx>]

Folks,
   I need a bit of help with removing E30 cloth seat covers. The bottom
cushion upholstery on my seat has worn through and I've finally purchased a
replacement. 
   The old cover is pulled over the metallic hocks on the front and the
sides of the bottom cushion. Then the back flap goes over the rear and under
the cushion and is impaled on a bar under the seat. My difficulty is with
removing that bar and freeing the old cushion.
   The bar may be held in place by a round plastic/metallic plug on one end.
However, I am having difficulties removing or even nudging the plug. 
   If anyone has successfully disassembled the bottom of their E30 seats,
please give me some hints on removing that bar. 

TIA,
Alex

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