How to Properly Size based on distance?

I'm attempting to make this script where the local Brick's BillboardGui's Frame will resize based on their position, so no matter where they are, they'll be able to see it. Line 20 never seems to work. Without all of the extra work, I'd see the part fine. I tried to use coroutine (Not sure if I should. First time using it), but it doesn't fire/I don't know it doesn't due to me not seeing the brick.

local Sizing = coroutine.wrap(function()
    pl = game.Players.LocalPlayer
    c = game.Workspace.CurrentCamera
    s = c.Part
    f = c.Rank.Frame
    old = 0
    while true do
    if (old < (pl.Character.Torso.Position - s.Position).magnitude) then
        f.Size = f.Size + Vector3.new(.1,0,.1,0)
        old = (pl.Character.Torso.Position - s.Position).magnitude
    elseif (old > (pl.Character.Torso.Position - s.Position).magnitude) then
        f.Size = f.Size + Vector3.new(.1,0,.1,0)
        old = (pl.Character.Torso.Position - s.Position).magnitude
        end
    end
end)

game.Players.PlayerAdded:connect(function(p)
    p.CharacterAdded:connect(function(c)
        game.Lighting.Part:clone().Parent = game.Workspace.CurrentCamera
        Sizing()
    end)
end)