I couldn't find a simple model of this extension without bearings so I made one myself because I ran out of place where to place spools lol. I only have one AMS lite and two A1/A1minis. I currently can have 8 spools placed around them for quicker filament swap. Check out my Bambu A1 mini filament enclosure where the spool goes under the printer. The print profile is made to be strong and quick at the same time - adaptive layer height only for neccesary parts of the components.