Remember you have to trick bambu studio by configuring your source as the external spool, it will become a little hard to follow with multiple sources. You will have to disconnect from the feeder, pass the filament through the hole etc, it would be just a simple extra step to just transfer the spool in the AMS-HT rather than complicate things drilling holes in the AMS cover, add some PTFE tubes etc and put a plug there when you don’t use it.