Hi ChanCafun, nice pics of your system.
Which Level Troll are you using? Have you had any deployed for any period of time. I’m currently working with Level Troll 500.
I’m also looking at the RS485. The real issue is the power management, and generating a switched +12V that is typically required in a RS485 level-troll or Keller Nano-level, oh, and of course doing it off a Li-Ion or its more enviro friendly cousin LiFePO4 battery.