--- a/src/newgrf_commons.cpp	Fri Feb 08 16:25:55 2008 +0000
+++ b/src/newgrf_commons.cpp	Fri Feb 08 16:56:52 2008 +0000
@@ -91,11 +91,6 @@
 		}
 	}
 
-	/* No mapping found, try the overrides */
-	for (uint16 id = 0; id < max_offset; id++) {
-		if (entity_overrides[id] == grf_local_id && grfid_overrides[id] == grfid) return id;
-	}
-
 	return invalid_ID;
 }
 
@@ -169,6 +164,24 @@
 	}
 }
 
+/** Return the ID (if ever available) of a previously inserted entity.
+ * @param grf_local_id ID of this enity withing the grfID
+ * @param grfid ID of the grf file
+ * @return the ID of the candidate, of the Invalid flag item ID
+ */
+uint16 IndustryOverrideManager::GetID(uint8 grf_local_id, uint32 grfid)
+{
+	uint16 id = OverrideManagerBase::GetID(grf_local_id, grfid);
+	if (id != invalid_ID) return id;
+
+	/* No mapping found, try the overrides */
+	for (id = 0; id < max_offset; id++) {
+		if (entity_overrides[id] == grf_local_id && grfid_overrides[id] == grfid) return id;
+	}
+
+	return invalid_ID;
+}
+
 /** Method to find an entity ID and to mark it as reserved for the Industry to be included.
  * @param grf_local_id ID used by the grf file for pre-installation work (equivalent of TTDPatch's setid
  * @param grfid ID of the current grf file

--- a/src/newgrf_commons.h	Fri Feb 08 16:25:55 2008 +0000
+++ b/src/newgrf_commons.h	Fri Feb 08 16:56:52 2008 +0000
@@ -49,7 +49,7 @@
 	virtual uint16 AddEntityID(byte grf_local_id, uint32 grfid, byte substitute_id);
 
 	uint16 GetSubstituteID(byte entity_id);
-	uint16 GetID(uint8 grf_local_id, uint32 grfid);
+	virtual uint16 GetID(uint8 grf_local_id, uint32 grfid);
 
 	inline uint16 GetMaxMapping() { return max_new_entities; }
 	inline uint16 GetMaxOffset() { return max_offset; }
@@ -72,6 +72,7 @@
 			OverrideManagerBase(offset, maximum, invalid) {}
 
 	virtual uint16 AddEntityID(byte grf_local_id, uint32 grfid, byte substitute_id);
+	virtual uint16 GetID(uint8 grf_local_id, uint32 grfid);
 	void SetEntitySpec(IndustrySpec *inds);
 };