Pear Effector for Kossel Plus - with ABL

This is the final version for my "pear effector" for Anycubic Kossel Plus.
This version uses Auto Bed Leveling but no Zesty Nimble, look for other version here:
https://www.thingiverse.com/thing:3255063 (no ABL, no Zesty Nimble)
and
https://www.thingiverse.com/thing:3255093 (with ABL and Zesty Nimble).

Fans angles have been studied with CFD simulations in oreder to maximize air flow and heat sink cooling.
It uses E3D-v5 heat sink from Anycubic original kit (it is an E3D-v5 clone) and
- 3x 30x30mm fans;
- 9x M3 nuts;
- 2x M3 screws;
- 1x 20mm X 10mm X 2mm magnet;
- 12x 5mm (diam) X 5mm (height) cylindrical magnets;
other components are from Anycubic kit.

This effector works better than original Anycubic one since air flow is better oriented toward heat sink and then to nozzle, all around. Consequently
- 3D printed surface is smoother because of better air flow all around
- it is far away difficult to clog the throat, heat sink is better cooled down

Using magnets t