Re: battery drain
OK the "safe" way requires a jumper cable. Start on the 10A scale/connection. When you see it drop under 200 ma (0.20) then
1) connect the jumper cable across the leads
2) change the meter & input to the 200ma scale
3) remove the jumper
or just use the 10A scale for the whole procedure, can usually read to 10 ma and that is enough to see issues. Just make sure it goes to zero when disconnected.
Key and lights must be off. If interior lights are on wait for them to time out.
ps I do not claim genius at all. Others may...
Was a lot easier when cars were dumb.