Randomize position for 5 elements in a 3x6 table

I'll keep this simple as not to waste your time.
I have 5 elements which I want to distribute into a 3 row high, 6 column wide table without overlapping.

The positions are designated by [x,y] coordinates.

The position of these elements changes with each tick of a Timer component.

The elements are of the TImage type.

I thought about having an array of points from which a point gets deleted if its chosen during a step-by-step process of assigning the values for each element, but I'm not sure arrays work that way.