I am trying to get a very low consumption Arduino Pro Mini 3.3V and I read that removing the LED and regulator will lower the consumption. Where do I find a very safety guide for doiing such thing?
If you power through the Vcc pin the regulator and the LED will draw current. By removing the Led and 5V regulator you will remove this current draw and it's a nice win in sleep mode. (will get you toward 1.5µA on a 8MHz board or 3µA for a 16MHz one).
have you identified where the 2 components to remove are?
For the regulator it's OK if you only unsolder and lift up the Vout tab, then there is no current draw.
if you are lucky, some boards have a very convenient strap which will disconnect the regulator and the LED, in this case, just cut this strap (remove the solder bridge) and you are done.
➜ if you are worried about doing this, find a Pro Mini with the strap, that will make your life easy.
Why do you need a guide? It is only 2 components, and due to the meny clones of this board, a guide would be near impossible.