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Hello.

We found exactly the same thing, the GTM is very complex! As such we came to the same conclusion and decided to also sick with the normal GA system.

I did get GTM working though but found the results it provided to be not a great deal better.

Have a nice day.

Paul Hughes.

Hello.

If you have your google tag manager code published already on your site all you need to do is add some additional code for the ecommerce features, which can be found at: https://support.google.com/tagmanager/answer/6106097?hl=en

We found that this was not the only way to do this and we found GA's own tracking to work much easier than via Tag Manager.

Paul Hughes.