The idea published by Scigola (https://www.prusaprinters.org/prints/151610-anycubic-i3-mega-sostegno-cablaggio-estrusore) is pretty good! However, the Anycubic i3 Mega S is shipped with a 12mm Diameter wire sleeve. This and the bowden tube often get tangled up in the Z-portal. That's why I adopted the fundamental idea and designed it for the larger sleeve diameter and angled it back to give the wire harness and the bowden tube a push to the rear. Much better than plates at the frame which usually don't work well either. As there is close to no space it took me a few attempts to find a solution which works. Nice side effect: as longer I tinkered around as simpler it turned out, fast to print and with a print orientation which makes it less prone to breakage. No idea whether the original allows full print height but I seriously doubt it. All I used from the original design was the bracket which I butchered a bit.

Print parameters:

0.15mm layer height and adaptive layers

Infill 30% cubic with double line

Support everywhere

Material PETG (or ABS/ASA but PLA might be sufficient too).

As I print PETG pretty slow print time was ~20 minutes.

The bracket is attached in the 2 holes with a new tie wrap (cable tie) but two M3 screws and nuts could be used too. To hold the harness in place a small tie wrap is used thru the hole to hold the sleeve.