Hi @timsullivan ! As far as I understand embedding it as an iframe should not stop this from working.
You will need to use the following code in your case: document.querySelector(‘input[name=gclid]’).value = “valuehere”; as the name of your input field is gclid, and not cid as it was jennaovett.
When using this method the name of your input field will generally be the same as the label in HubSpot, so if the label is gclid you should use name=gclid, if the label were utm_content you should use name=utm_content.
Hopefully that helps 