How do I dynamtically add and position CheckBox elements in WPF?

So here is the deal, I started making a WinForms application to display a grid of 4*4*4 checkboxes, representing a real-life 4^3 grid of LEDs.

This is what it looks like right now: http://ift.tt/1Cc5o61

I want to convert this to an WPF app, so that I can use the transparency option of the WPF Checkbox, to make the non-selected layer [there will be 4 layers] of checkboxes slightly transparent, to give it a more true 3D feeling.

I am new to WPF and I have tried to nest 2 elements in the main Window [for example, 2 grids to slightly overlap the position, by maybe 20 pixels, so that they would appear to be 3d-staggered], but it simply won't let me do that, and only lets me add a child grid inside the original grid.

TLDR: How can I dynamically create lots of checkboxes while giving them absolute pixel positions?

My current working WinForms C# code:

int spacing = 25;
    for (int z = 1; z <= 4; z++)
            {
                List<string> zString = new List<string>();
                for (int y = 1; y <= 4; y++)
                {
                    for (int x = 1; x <= 4; x++)
                    {

                        int pixel_x = zero + ((x - 1) * spacing);
                        int pixel_y = (zero - 4) + ((y - 1) * spacing);

                        //int id = ((y - 1) * 4) + x;

                        CheckBox box = new CheckBox();
                        box.CheckStateChanged += new System.EventHandler(checkBox2_CheckedChanged);
                        box.Tag = id;
                        zString.Add(id.ToString());
                        //box.Text = id.ToString();
                        box.BackColor = Color.Transparent;
                        //box.
                        box.AutoSize = false;
                        box.Size = new Size(20, 20);
                        box.Padding = new Padding(3);
                        box.Location = new Point(pixel_x, pixel_y);

                        this.Controls.Add(box);
                        id++;
                    }
                }