You always get twats. Not worth pissing off every driver who passes you because of the odd prick.
Deal with idiots as and when they pass you.
Cameras are a good idea. homemade, idiotic contraptions are just that.
Trouble is, it's not just the "odd prick". Cycle just a couple of miles these days and you will get several close passes. There are so many more cars on the road now and since the start of social media, people are less patient and are generally in a bad mood...or just plain distracted trying to write a Whatsapp while they drive. Add to that click bait media jocks who want to sir up trouble and vilify people who happen to be on bikes.
I've run cameras, but often the police just aren't interested in doing anything. Hence I've found it's best to ensure people keep their distance in the first place, rather than try and persuade the police to take action afterwards. Trevor's first attempt might be a bit long, but I've found something like this is the only way to get people in cars to give room. There are commercial products too, the original Oxford stalk, or the more modern "L-bow".
What's the alternative? This?
www.pedelecs.co.uk