I took RubenKan's advice and was able to solve the problem using RemoteEvents. There are three parts to my system
1: The original GUI LocalScript inside of StarterGui I replaced the part of the script that changes the size and position with remote:FireServer("the info"), which sends the information to the server.
2: A new Script inside of ServerScriptService This new script uses remote.OnServerEvent and then fires all the clients with :FireAllClients(info).
3: A new LocalScript also inside of StarterGui with the GUI script This script uses remote.OnClientEvent that connects to a function with if statements for what has to be done according to the original string.