Simultaneously Assigning Brushes to Multiple Images on a Widget

I am currently in the process of making a luck-based card game based on the card game blackjack, which makes use of grids of cards.

With the two integers - Randomizer and CardNumber - set to 1 as the Minumum for the two nodes that randomly select from the two ranges, the program determines which suit of cards will be played.

Then, the CardNumber is used to decide which card should appear as the image.

So my question is this: what’s the fastest and least complicated way to assign images to every image for each card, as shown here?

After taking some steps back, I decided to work with arrays to make the coding less messy and complicated.

Here is what I have, so far. Now I want to assign a number between 1 and 13 to each card button for the time being, then assign a brush to an image which will be in a separate array later. What would you recommend I do next?