I had one of those sitting in a drawer for years. I think i did get OpenWRT on it at one point. Eventually it just stopped working altogether, but i felt like i got more than my money's worth out of it. Even brand new that router cost next to nothing.
the idea is more to get into hardware hacking.. the hardware is kind of irrelevant ... the most important thing is a sane UART exposed, documentation, videos about it and etc..
Funny enough i have the same multimeter too
wait until somebody read it.. its one vibe coding session away from done..