I would also like to add one more mod I did. I don’t think it has been listed on this thread. Being an electronic tech, I was annoyed by the stock battery indicator that just offered the 4 lights showing how much charge is left. I installed this battery meter. The link is below. For under $20 and fairly easy to install, it shows actually voltage and power being consumed. By adding a DPDT switch, it will also show charging current. That is what the small red switch is in the photo. I have really liked it.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1