Unable to perform UDim2.new in this case?

I am making parts in my game simulate a humanoid in a way. I put a health value in each part (partinstance).

When the the part's health value changes.. I put a enable the Parts "Health bar Billboard Gui". I get the health's percent by doing local percent = math.floor(Health.Value/MaxHealth*100)/100

I then use the percent variable here. "green" is the green overlay frame you usually have on health bars. The green overlay will vary in size depending on the percent of health.

green.Size = UDim2.new(percent, 0, 1, 0) 
green.Position = (UDim2.new(0, 1 - percent, 0, 0)), "Out", "Quad", 1, false, nil 

However, the only thing the script isn't doing is exactly that. My test prints stop at those lines and does not give any other errors. Am I doing this incorrectly?

Here is my hierarchy of the Billboard Gui. http://prntscr.com/7vyoc0

Here is my full script.

local MaxHealth = 100
HealthDisplay = game.ReplicatedStorage.HealthDisplay:Clone()



function AddHealthModule(partinstance)
	local Health = Instance.new("IntValue", partinstance)
	Health.Name = "Health"
	Health.Value = MaxHealth
	local display = HealthDisplay:Clone()
	display.Parent,display.Adornee = partinstance,partinstance
	
	local percent = math.floor(Health.Value/MaxHealth*100)/100
	local green = display.back.green

	
	Health.Changed:connect(function()
		local display = Health.Parent.HealthDisplay
		display.Enabled = true
		display.back.HealthTxt.Text = "Health"..Health.Value.."/"..tostring(MaxHealth)
		green.Size = UDim2.new(percent, 0, 1, 0) --Doesn't work?
		green.Position = (UDim2.new(0, 1 - percent, 0, 0)), "Out", "Quad", 1, false, nil --Neither does this
		if Health.Value <= 0 then
			partinstance:Destroy()
		elseif Health.Value > MaxHealth then
			Health.Value = MaxHealth
			display.HealthDisplay.Enabled = false		
		end
	end)
end
return AddHealthModule