Google Tag Manager installation

I’m having an issue with Google Tag Manager.

I’ve been able to install the code into the Header with no problems, and I used the guide linked here to install the other code sinppet. However, the snippet that is meant to go immediately after the it is embedded within an iframe:

This is a no-no to Google, as it doesn’t recognize the second Code and will give me an error. Has anyone been able to create a workaround for this?