I tried to disable the CoreGuis and it did get rid of the tool bar, the problem though was that if I tried to equip a gear or tool nothing happened.
Make a GUI that interacts with the items, you will still need some form of Player UI or in-game object for interaction with the models, unless you script it so that you can use buttons like "e" to equip your item or arrows to switch. This process requires some creative coding on your part.
Make an interacting GUI and then it can interact with models, and tools.