@SaeedHamza
Thank you very much for this video which goes an entirely different way to solve the problem.
The pivotal key to this approach is to split the surface to make it selectable.
Another important thing I could learn is the possibility to move one surface to another one using the Replace Face tool.
This method is universal to all slots, no matter how wide they are. I need the distance to the upper surface to be all the same. This is important to melt the entire end of the slot to the surface when printing.
The only thing I miss, is the audio as I know how good you are explaining, what makes it easier for a beginner to follow the steps. Nevertheless, the video is perfect, I only had to watch it several times 😉
Regards
Michael