I use several different telescope setups with 3 different cameras, with or without filters. Sometimes it´s hard to find or remembering the start position for the focus.
Therefore whenever I change a setup and found the focusser position I measured the space and designed and printed a marker ring. This gives a good start position for the focus fine tuning.
You need to re-design the height of the marker for your setup. Therefore I have uploaded the design in different formats. Hope there is one for your favorite design tool. I used Fusion360.

Artillery Sidewinder X1

No

No

0.2mm

25%