What you need to make it work:

1 x (688ZZ) Ball-bearing : https://s.click.aliexpress.com/e/_DeYwlFN

1 x Motor : https://s.click.aliexpress.com/e/_DlR1NNv

1 x Powerswitch : https://s.click.aliexpress.com/e/_DnL3Rax

1x 2Slot Batterieholder : https://s.click.aliexpress.com/e/_DDAHg4x

1 x Potentiometer : https://s.click.aliexpress.com/e/_DmtLP1t

1 x Rubber with the right strength, like : https://s.click.aliexpress.com/e/_DDvOxlv

A file , the parts can be very tight, supported surfaces, elephant feets,… must be filed off. (use something like that: https://s.click.aliexpress.com/e/_DdVqiaB )

Optional (but recommended):

1 x LED White : https://s.click.aliexpress.com/e/_DDmBrGn

Some plastic glue (i recommend Revell: https://amzn.to/3DFFAFY )

Tools:

Soldering iron ( like : https://s.click.aliexpress.com/e/_DClaicF )

An hotglue pistol with some hotglue ( like : https://s.click.aliexpress.com/e/_DCyS44j )

A file ,the parts can be very tight, supported surfaces, elephant feets,… must be filed off, the parts may not fit otherwise. (like: https://s.click.aliexpress.com/e/_DdVqiaB )

You can use the same parts for this rotary plate:

To attach the LED for the display illumination. Print out an LED holder and stick it in front of the board in the direction of the display, then fix the LED with a little hot glue.

Make sure you have a good cable guide for the assembly, no cables should touch the belt or the drum, so only use as many cables as can be pulled off the back and placed directly next to it. either use additional LED holders to which you can then fix the cables with hot glue.