Pistol position R6 to R15 how to fix my arms?

I'm not sure to have well understood the concept lol:') Somebody could help me to understand how to fix this?

Problem: PICTURE

local Arms_Made

Tool.Equipped:Connect(function(Mouse)
    if Character and not Arms_Made then
        Arms_Made = true
        local UpperTorso = Character:FindFirstChild('UpperTorso')
        --< LeftHand
        Left_Weld = Instance.new("Weld", UpperTorso)
        Left_Weld.Name = "Left_Weld"
        Left_Weld.Part0 = Character.Head
        Left_Weld.C0 = CFrame.new(0, -1.5, 0)
        Left_Weld.Part1 = Character["LeftHand"]
        Left_Weld.C1 = Settings.LeftPos
        --< RightHand
        Right_Weld = Instance.new("Weld", UpperTorso)
        Right_Weld.Name = "Right_Weld"
        Right_Weld.Part0 = Character.Head
        Right_Weld.C0 = CFrame.new(0, -1.5, 0)
        Right_Weld.Part1 = Character["RightHand"]
        Right_Weld.C1 = Settings.RightPos
    end
end)