MacOS – How to access “hidden” .help files

Some years ago I created a Project (using Xcode 3 under OS X 10.6) and created a Help File, naming this MyApp.help in accordance with the tutorial.

Under more recent OS Apple (in its infinite wisdom) decided to make all .help files packages and not display contents. You could still see the contents in Finder with Show Package Contents.

In El Capitan the contents of .help files seems to be hidden, but seemingly not in the fashion that was previously used to hide files such as ~/Library.
(It is still possible to display Package Contents in the finished .app to see these, so the intent does not seem to be to hide these from the end user.)

How do you get access to these files to modify contents and/or add new files? They are still there, and can be seen in the Terminal. cd PathToMyApp/MyApp.help/Contents/Resources

Edit
I was exploring the suggestions, without much success. After some trials I rebooted and could no longer see the files in Terminal.

I have a backup to an external HDD (using rsync) and could see all the files when mounted on Linux. (I can also load and edit in BBEdit through a Project).

I just tried again and they were all back in Terminal.