Failing Action<Car> To Action<List<Car>>, C#

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//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace Rextester
{
    class Program
    {
        public static void Main(string[] args)
        {
            var car = ExpectCar(model =>
            {
                foreach (var type in model.Types)
                {
                    type.Name = "SuperStarShineType";
                }
            });
        }

public static Car ExpectCar(Action<Car> preProcessor)
        {
            var car = new Car();
            preProcessor.Invoke(car);

var carList = new List<Car> { car };
            var carActionList = new Action<List<Car>>(list => list = carList);

return ExpectCars(carActionList).Single();
        }

public static List<Car> ExpectCars(Action<List<Car>> preProcessor)
        {
            var carList = new List<Car> {
                new Car {
                    Types = new List<Type> {
                        new Type {Name = "SuperCar"}
                    }
                }
            };

preProcessor.Invoke(carList);

return carList;
        }

}
    class Car
    {
        public List<Type> Types { get; set; }
    }

public class Type
    {
        public string Name { get; set; }
    }
}

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Compilation time: 0,16 sec, absolute running time: 0,11 sec, cpu time: 0,09 sec, average memory usage: 16 Mb, average nr of threads: 3