As your description references a box, which is a three dimensional object, it is practical to consider to use software which assists/implements three dimensional object design.
Depending on your willingness to devote hours to learning a software package, you can use a beginner level program that will take little time to learn and may provide your requirements, or you can use many hours to use a high end engineering package.
It's also practical to use a lower grade program to create prototype models and move on to more advanced programs as your requirements increase.
To that end, consider to examine a program known as Tinkercad. It allows the user to drag and drop primitives to a workspace, editing and resizing and placing to generate three dimensional models.
I use Tinkercad to "build" models to better visualize the placement of components which will later to transcribed into a more technical parametric program. It reduces my error factor substantially and reduces workload as well.
You could "graduate" to Onshape for more advanced model creation, including automatically created drawings based on your models. Both of these programs are web based and no cost.
Another step up in the learning curve, accompanied by additional features and capability is Fusion 360. This program is free for hobbyists and small businesses and is partially web based, but uses a client package installed on your computer.
All of the above programs have tutorial videos available on the YouTube, allowing you to observe others work and progress and better decide which is best for you.