diff --git a/src/saveload/saveload.h b/src/saveload/saveload.h
index 3ab4a0af4e..04babb9c1d 100644
--- a/src/saveload/saveload.h
+++ b/src/saveload/saveload.h
@@ -1318,6 +1318,7 @@ int64_t ReadValue(const void *ptr, VarType conv);
 void WriteValue(void *ptr, VarType conv, int64_t val);
 
 void SlSetArrayIndex(uint index);
+static void SlSetArrayIndex(const ConvertibleThroughBase auto &index) { SlSetArrayIndex(index.base()); }
 int SlIterateArray();
 
 void SlSetStructListLength(size_t length);
diff --git a/src/script/api/script_list.hpp b/src/script/api/script_list.hpp
index 64eb6d821c..0570364e24 100644
--- a/src/script/api/script_list.hpp
+++ b/src/script/api/script_list.hpp
@@ -43,13 +43,19 @@ private:
 	int modifications;            ///< Number of modification that has been done. To prevent changing data while valuating.
 
 protected:
+	/* Temporary helper functions to get the raw index from either strongly and non-strongly typed pool items. */
+	template <typename T>
+	static auto GetRawIndex(const T &index) { return index; }
+	template <ConvertibleThroughBase T>
+	static auto GetRawIndex(const T &index) { return index.base(); }
+
 	template <typename T, class ItemValid, class ItemFilter>
 	static void FillList(ScriptList *list, ItemValid item_valid, ItemFilter item_filter)
 	{
 		for (const T *item : T::Iterate()) {
 			if (!item_valid(item)) continue;
 			if (!item_filter(item)) continue;
-			list->AddItem(item->index);
+			list->AddItem(GetRawIndex(item->index));
 		}
 	}
 
@@ -99,7 +105,7 @@ protected:
 					/* Push the root table as instance object, this is what squirrel does for meta-functions. */
 					sq_pushroottable(vm);
 					/* Push all arguments for the valuator function. */
-					sq_pushinteger(vm, item->index);
+					sq_pushinteger(vm, GetRawIndex(item->index));
 					for (int i = 0; i < nparam - 1; i++) {
 						sq_push(vm, i + 3);
 					}
diff --git a/src/script/squirrel.hpp b/src/script/squirrel.hpp
index b816f81216..712f40897c 100644
--- a/src/script/squirrel.hpp
+++ b/src/script/squirrel.hpp
@@ -11,6 +11,7 @@
 #define SQUIRREL_HPP
 
 #include <squirrel.h>
+#include "../core/convertible_through_base.hpp"
 
 /** The type of script we're working with, i.e. for who is it? */
 enum class ScriptType : uint8_t {
@@ -110,6 +111,8 @@ public:
 	 */
 	void AddConst(const char *var_name, uint value) { this->AddConst(var_name, (int)value); }
 
+	void AddConst(const char *var_name, const ConvertibleThroughBase auto &value) { this->AddConst(var_name, static_cast<int>(value.base())); }
+
 	/**
 	 * Adds a const to the stack. Depending on the current state this means
 	 *  either a const to a class or to the global space.
@@ -152,6 +155,7 @@ public:
 	void InsertResult(bool result);
 	void InsertResult(int result);
 	void InsertResult(uint result) { this->InsertResult((int)result); }
+	void InsertResult(ConvertibleThroughBase auto result) { this->InsertResult(static_cast<int>(result.base())); }
 
 	/**
 	 * Call a method of an instance, in various flavors.