Identify contours on boxes so that I can deskew for EasyOCR

Appreciate some help please. I have been working on this for a month but cant seem to get anywhere. I checked multiple stackoverflow/blog posts, have started a course in computer vision and completed the OpenCV section but still getting nowhere.

I am trying to read the labels on boxes on a pallet in a warehouse - image below. EasyOCR does OK on the raw image and grayscale and much worse with any other pre-processing steps. I understand I need to deskew to improve results but struggling to find the individual boxes edges or even the overall edges of the pile of boxes. Any thoughts / help would be appreciated please.

I see in the following post the author was recommended to try a neural network approach. Is there anything I can do in OpenCV or should I scrap what I have done and look at neural networks/ YOLO/ SSD?