How can I add support for a type that references itself for a custom Reader/Writer?

I am creating a pathfinding system that I want to work with my Multiplayer game. I am using Mirror to handle networking. I created a custom Reader/Writer class so that I can send my custom type (OverlayTile) to my server.. If I don't create that custom Reader/Writer class, I get: Use a supported type or use a custom reader (At OverlayTile). .. I did create a custom Reader and Writer (I'll share below), but my question is: My OverlayTile class has a field OverlayTile previous .. I am not sure how to go about adding support for this field that references itself. The other properties have something like reader.readInt() but how could I do something similar like this for my OverlayTile type?

I have a class called OverlayTile which looks like this:

public class OverlayTile : MonoBehaviour
{
    public int G;
    public int H;

    public int F { get { return G + H; } }

    public bool isBlocked;

    public OverlayTile previous;

    public Vector3Int gridLocation;

   
}

My Reader/Writer class looks like this:

public static class OverlayTileReaderWriter
{
 
 public static void writeOverlayTile(this NetworkWriter writer, OverlayTile overlayTile)
 {
     writer.WriteInt(overlayTile.F);
     writer.WriteInt(overlayTile.G);
     writer.WriteInt(overlayTile.H);
     writer.WriteBool(overlayTile.isBlocked);
     writer.WriteVector3Int(overlayTile.gridLocation);     

 }


 public static OverlayTile readOverlayTile(this NetworkReader reader)
  {

      return new OverlayTile
      {
          G = reader.ReadInt(),
          H = reader.ReadInt(),
          isBlocked = reader.ReadBool(),
          gridLocation = reader.ReadVector3Int(),
         // previous = overlayTile.GetComponent<OverlayTile>()  ??



 }; 

  } 

}