Set up google dynamic remarketing

Hello!

I am trying to set up dynamic remarketing in google ads, I am using your article for guidance: https://gtm4wp.com/how-to-articles/how-to-setup-dynamic-remarketing-in-google-adwords
(btw I am using Woocommerce)

I have a few questions:

1) In your article you recommend that we check the box “use SKU instead of ID”.
On our site this is the info that I have about a product:

Example- https://bluegaz.se/produkt/stek-wokjarn-polerat-40cm/
SKU: 806540 (“sku”)
Product ID: 1076 (“id”)
EAN: 8411470004825

In my google shopping product feed I have the following attributes included:
Google shopping attributes: g:id -> value: Product Id
Google shopping attributes: g:gtin -> value: woosea ean (added custom attribute)
(my product feed is working well and I have had no issues)

So, I do not really have an attribute in my feed for the “sku”, as far as I can see.

So my question is, should I really check the box “use SKU instead of ID”, it doesn’t feel correct? Maybe I’m missing something?

2) Also, I am really unsure about whether or not I need to enter a “prefix” for my product ID:s?

Thank you very much for your help!

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