To begin here are some general

Found at: zaibatsu.circumlunar.space:70/~visiblink/phlog/20210215

tfurrows, re: measuring for outlets, light fixtures, etc.

To begin with, here are some general principles: think of 
everything as a grid. Rely on a square to find the positions 
n the grid.

Here's a little ASCII art depicting a traditional L-shaped 

|                 |
|                 | |
|                 | |
|                 | |
|                 | | <-- square
|                 | |
|                 | |
|                 | -----------
|                 |        --
|                 |       |  | <-- fixture
|                 |        --
|                 |
|                 |
|                 | <-- neighbouring panel

Let's say that you're installing the panels vertically and 
you've installed panels from left to right along a wall. 

neighbouring panel and line the other up with the bottom of 
the fixture that you need to cut a hole for. Then:

edges of the fixture.


Now, when you measure for the hole on the new panel, the 
measurements (from the bottom of your panel) for the bottom 
and top of your hole. The distances that you measured over 
from the neighbouring panel in step two are measurements 
from the left side of the panel to the the sides of your 
the square), they will intersect at all the corners.

lid and center it inside the lines. Then trace around it. If 
the hole is hexagonal, just wing it by drawing in the cuts 
across the corners (or grab another electrical box and trace 
around it).

You can also make all of the measurements out of a corner, 
or from the ceiling downwards, etc.