+1 reading & learning are something you should be doing daily.
when you rush things you will make mistakes.
Never believe everything you see on the web or youtube.
get multiple sources to confirm your finding/search results etc.
After that 'learn by doing'.
"measure 10x cut once"
I havent got around to reading up on ECU.
Hopefully somebody that has tactrix & laptop hooked up to their ECU can chime in.