Mk2B Bed Modification for Anet A8

I upgraded my heated bed to a Mk2B heater pcb and borosilicate glass plate recently, thought I'd share the construction information and the printable parts.

Why upgrade? The aluminium plate is heavy, and because it heats up unevenly (hotter in the middle and cooler at the edges) it warps, making printing difficult, especially when you want a 0.1mm first layer.

The borosilicate glass makes an excellent build surface, and because it has a very low coefficient of thermal expansion it stays ve