Noel - 
I recently rebuilt the heater box and battery tray area on the Sprite.  At
the last minute I decided to look for that spacer.  In the camping gear I
found an old pad used under sleeping bags - kinda a half inch foam.  All
that was needed was a good pair of scissors and it was cut to the right size
and hole.
Check a camping store for an piece of mattress foam or something.  The stuff
I used seemed to be pretty resistant to the heat.
Hope this works out!
Jason.
|    Jason Urban - APOGEE LABS  215-699-2060     |  
|    CA Studio  www.dynanet.com/~crackerarts     |
|  '95 Z/28 6spd  '65&'67 Austin-Healey Sprites  |
 
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