lots of good advice already on top
nothing much for me to chip in
except for the fact that, while whatsapp is a good repository for info n docs n drawings of sort.....it'll get messy if too much info is bundled in, you'll prolly need separate groups for each process / part

Method of Statement tak betul la ni....sapa author HQ?
who has the authority to shoot HQ?
that 200page work instruction / docs is sitting where? Company shared folder, (electronic) library/database? just have to properly re-write back these instructions into a more detailed but concise doc detailing out each n every necessary step.

btw, apa barang la u pasang?