# Final Assembly

## Step 1: Trim the LED Matrix header pins

Stack the Core Board into the LED Matrix and trim the 8 pins extending from the LED Matrix board if they are longer than the Core Board pins. After trimming (if needed), they should look like this:

![](https://699013105-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MQdPFfouM2ulKSFIJJM%2F-MhvHZmj8Xx083Jnytio%2F-MhvIFq_Ig3MMbH8peA-%2FIMG_3778%20LM%20and%20CB%20Pin%20lengths.jpeg?alt=media\&token=918858c7-4dde-4ada-9990-13ebf6ded848)

## Step 2: Stack the Boards

On the bottom is the Logic Board. Next up is the LED Matrix, and on top of that is the Core Matrix whose pins slide through the LED Matrix to connect to the Logic Board. The stack-up looks like this:

![](https://699013105-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MQdPFfouM2ulKSFIJJM%2F-MhvIfyoYMfbDtjjuHv2%2F-MhvJlKg9PTNNullR4_Z%2FIMG_3781%20Stacked%20side%20view.jpeg?alt=media\&token=c91d1113-24c7-4381-a2ff-1db35ef97ecd)

Optionally, you can place diffuser sheet layers between the LED Matrix and the Core Board. They can be held in by soldering in single pin headers in the LED Matrix board J3/4/5/6 positions. Those pins are exclusively there to provide a mechanical mounting point for diffusers. They have no electrical connection.

I do not recommend soldering the Core Board header pins to the LED Matrix board. Except for, optionally, SCL/SDA/3V3/GNDD if you intend the make use of the QWIIC port on the backside of the LED Matrix board. Those signals are also routed to the top and bottom edge of the LED Matrix as 0.1" 4-pin header rows.&#x20;

