In other words, I’d like to leave the button icon in place on the right, but place an image with the text I type in the callout heading or subheading.
You can use an image in the Heading / Sub-Heading
How difficult would this be?
It is easy. Now it depends what you want. I have tried the following code in the Prana Callout Heading and it is working fine,
Now try by yourself.