How to weld a part that I put inside a player?

I was wondering how to weld the part to the player inside his head when it spawns.

local fake = Instance.new("Part")
fake.Size = Vector3.new(1, 1, 1)
fake.Parent = player.Character.Head
fake.CanCollide = false -- does this break it?
fake.CFrame = CFrame.new(player.Character.Head.Position)
fake.Transparency = 1
print("Made Brick!")

I am just wondering how I would weld it after It spawned within their head. Also, can i have CanCollide to be set to true?