Nitrogen Gas Mask Help Needed

[SadCryingBunny]

Hi, please refer to the Photo for reference. I have the nitrogen cylinder and gas transfer hose/connections and a OTS Spectrum SCUBA Full Face Mask. However I am finding the thought of dying with a full face mask claustrophobic. I am wanting to try those smaller medical mouth/nose masks shown in the second picture and make it seal well by taping the exhaust open areas (exhales or air build up would leak from the silicone skirt) with a thin hose flowing from the mask to the 2nd stage scuba regulator mouthpiece which I will DIY attach myself or I can just hook it up to the flow meter with a hose attached to the nitrogen cylinder itself. I am planning on dying in my car in a very far away place. I will turn on the AC to the coldest (I like the cold, makes me feel cozy and sleepy), wear a nice warm jacket, watch a nice movie on my iPhone mounted on a magnet with rain sounds playing via Bluetooth on the other phone, eat ice cream, take sleeping pills, fall asleep and die in my car seat. I'll place the gas bottle firmly and restrain myself with my seat belt and bungee retainers so my hands can't rip the mask off while unconscious. I'm scared of the autopsy hence why I keep delaying this or until I can find a far away place in the bushes to setup my resting place. Otherwise can I go through Assisted Suicide in Switzerland for depression due to self harm scars? In Australia I am not eligible.
I found this online. I think it will work excellently. https://www.cpaponline.com.au/products/resmed-airfit-f20-full-face-mask

 

[eternalpace]

A second thread that refers people to this thread was created... but I'm bumping it anyway.