I finished building the Macharius!
The gallery can be found here: Warhammer 40k Macharius
I have also updated the pdf, so redownload that if you plan on building this beast! I suggest using atleast 200 gr/m2 paper for the larger parts, like the body, turret and tracks. 160 gr/m2 for the barrels in the hull and other small parts that need to be rolled.