I recently purchased the molded foam insert  from the Z store.  I am having trouble with it fitting properly at the arm rest area.  It seems to be too narrow in this area.  If you pull it over to fit over the armrest on one side then it pulls away from the other side.  Anybody else have this problem.  If so what did you do to make it work.  Looking for suggestions.

You need to warm up the new cover so it will stretch a bit, a hair dryer will work.

What grannyknot said. Another way to loosen them up is to get them out in the bright sun for a couple of hours. Another tip: turn the seat back cover inside out and roll it down over the foam and frame, don't pull it down.

No.  You don't understand, I can get the cover to fit ok.  It is the foam insert that is too narrow.  If I pull the foam insert over enough to cover one arm rest area and then pull the seat cover down then the molded foam does not cover the other arm rest area.  You can see the black metal seat frame in the picture where the molded foam insert is not covering the other side.

The seat back foam should have a channel molded into the foam that the round edge of the metal frame fits into.  This channel should be present on both bolsters and the headrest section of the foam.   Maybe take a picture of the back side of the seat back foam.

Have never used MSA''s foam.   What material is the dark area of the foam?

 

The black area is the metal frame where the molded foam does not cover the arm rest.  Yes, it has two channels, one on each side.  However if you pull one side to cover the arm rest area it uncovers the other side.  It seems to be too narrow.

That's odd. The foam backs from MSA fit perfect on the 1977 280z seats I put in my 240z so I could have the full recline / forward of the seat backs. Is your issue the same on both seat backs? Any possibility your metal back has been bent wider?

I finally just used some adhesive to hold the molded foam in place at the arm rest area.  I also placed some additional foam under the middle of the seat area where a gab was created after pulling the two sides into place.  This seemed to work out well.