Anycubic I3 Mega - hacking the gantry frame and carriage of hot end

This is a hack for the gantry frame such that the printer carriage will be risen for 28mm (say 25mm in my hack). After the hacking, the X-axis carriage of printer head and 2 end stops for Y-axis dual step motors will also be relocated (i.e. move down around 10mm by drilling two holes) to adopt the change for home (SET ZERO) by adjusting the vertical compensation screws.

First of all, tie bar of the gantry at the bottom of printer will be removed.
Second, gantry was shifted upward by removing