Sorry, I tried to upload a few pictures but was not successful. The tightest spots are if you are going from the Baths to Devil's Bay. The initial spot to lead you there is very tight and narrow. Adults either have to "duck" walk through or crawl. You do not have to go to Devil's Bay. The walk down to the Baths from the top isn't to narrow but is is rough & rocky. My son used his GOPro for a few minutes as we were walking down, I will see if he can get some images.
You can take another trail down to Devil's Bay and avoid the caves - we went down one way and came back the other and then did it again after lunch. My family of 4 was just there on Saturday and we explored all over (wish I had actually gotten some pictures of the caves and the baths - too busy exploring).