Anyway, we don`t have any schematics or block diagrams for D series yet (strange why..?)...
Also strange headaches problem. WiFi is so called low energy waves and this isn`t confirmed that have any issue to the health. I would suggest you to dissable wireless on your router if you fell better without wifi sources at your room instead of cutting of wires on TV`s reception module.
AFAIK the TV can`t be AP, it just have client mode.
Nowadays we can`t be 100% free from wifi/GSM/WiMAX signals in our living place, especially if we live in the city.
I know paranoiac people who made their living room by metallic nest to be free from those waves...