Get a friend to get rid of the items. Don't worry about them being his, just get rid of them.
Sleep if you are tired. Eat some food, drink some water. Have a long shower, get dressed.
You are doing it, you have done two weeks now. Remember that he is not feeling any pain about this, get angry if necessary.
I shouldn't tell you this but when I left my narc I did many things that seem undignified now but I still dont regret them:
He had been claiming benefits but working as a decorator- I shopped him to the tax, council tax and job centre.
He carried a large knife in his bag "for safety"- I shopped him to the police for knife crime.
He grew grass and sold it in the pub- ditto for supply.
I don't care if it made me look loopy, I relished the idea of his bubble being burst by knocks on his door to search his house/bag/bank account. I will never know if any of this came to anything but I am glad that I did it because it made me feel better.
I wrote to one of his exes, a letter I found difficult to write and agonised over for a long time. As a result we have become firm friends and she and I supported each other through the pain- he had messed her around for 23 years (I got out after less than one year) and was about to swoop on her again.
I am of course painted as the "viper" (I hear through the grapevine) but I dont mind one bit. If I have exposed any bit of his real self to the world, I am glad. Now, two years on from the final moment when I walked away and knew I meant it, I feel good about myself, I laugh at his pathetic persona and I know that I am well out of his nasty group of suppliers of narcissitic attention.
Keep passing the open windows.