Kossel - Unable to get the X, Y, Z, and Zero to be level

I have an Anycubic Kossel that was recently given to me by a friend. The friend had not used it in several years, so he gave it to me.

It has a problem with the print head hitting the bed when starting a print. I installed the latest Marlin version and used the recommended configuration.h for the Kossel. It continued to have the problem.
I followed the instructions in this youtube video from Chris Riley: https://www.youtube.com/watch?v=Xk7remEhUx8

I first set the height using 2 pieces of paper to determine when I found the right height, it ended up being 301.5.
Then I tried to level the the print head. For tower 1, I had to put the screw all the way in. For Tower 2 and 3, I had to almost screw them in all the way.

Now, when I go to zero, the print head sits ~8mm off the bed. The three tower positions all sit 2pieces of paper off the bed, but zero does not. If I adjust the height so that Zero is the right height, then the head drags when going to each tower position.

Just in case it needs to be said, the bed is perfectly flat (i.e. not bowed), it is made of glass with a grippy layer on top.

I'd appreciate any tips for how to get the head level everywhere on the bed.

re-zero the printhead.

any time you level a bed you will need to reset the z-calibration.

and use 1 sheet of paper not 2.

Okay, you might have done that.

sounds liek maybe the end stops aren't all at the same height. Or you might need to tension the belts and check the belt drive gears are tight to the stepper motor shafts. The grub screws can work loose.

I confirmed the belts are tight and there is no slipping.

I tried using the 'm665 z#' command to try and calibrate Z. But it seems to have no effect on anything.
It was initially set to 0, I changed it to 1 with no noticeable difference in the zero position, then I tried to 2, still nothing, then I tried 10, then 100, still no difference.

Is this not the right way to calibrate Z?

Current values:
M665 L218.00 R97.00 H298.10 S80.00 X0.00 Y0.00 Z100.00 A0.00 B0.00 C0.00

Tower 1:Attachment 17050Attachment 17051
Tower 2:Attachment 17052Attachment 17053

Tower3:Attachment 17055Attachment 17056
Zero: Attachment 17057Attachment 17058