OK,
 
  GC has two main sections (T_NODES) and the Standard OBJECT NODES.

  The only connection I see is in T_NODES like LASGN_NODE.  Where there
  is 'nd_vid'  Pointer to the receiving Object.  I have not been able to 
find a path
  by which the Recv Object gets traced.

  In other words are T_NODES traced (For GC Purposes) separately from the
object nodes?

  Chuck T.