How'd this work out for you in the end?
Was your implementation different? Still using this mod?
I am still working with it. I did notice it was a challenge to get all 8 adjusted so I dropped it to 5 (center and 4 cardinal points). Another change I made was to move to a larger metal washer against the heat bed, and a small steel one at the top of the spring. The spring was putting too much pressure directly on my printed ones, and the ABS and PETG washers I tried are a bit soft to take the spring directly. I will say for the first time, I am able to get a far more level bed than what it was at arrival.
thanks for the input... I am currently going to try 5-point level this machine with the existing hardware... but if I do decide to move ahead with this type of modification... there are a few thoughts that initially come to mind... like using insulating washers, creating a retention lip on the spring guide/spacer, and possibly using two shortened spacers (one at each end of the spring... probably integrating some form of integrated metal washer to equally distribute the pressure on the plastic parts...
I'll post back here where I end up.
Appreciate your time and reply.