How to track lightbox images

I am using Go Portfolio for a wordpress site and I would like to trak individual images shown in a lightbox type of popup

Chekc this for an example

http://go-portfolio.com/style-a/

I have no idea how to best do this. I tried content tracking but I am having difficulty to find the position to place ‘data-track-content’, ‘data-content-name’ and ‘data-content-piece’.

Would this be the best way to track this kind of content anyway? Or should I use a different method?

Would appreciate some help / insights

Kind regards

Anyone here that can offer me some help, would be much appreciated!

Kind regards