In case others are still interested in this topic, I found this INCREDIBLY helpful! I had a very complex dashboard with multiple elements that I wanted to redirect to a new WebMap and I was able to retain the integrity of all of my dashboard elements!
I simply went to this link https://ago-assistant.esri.com/ , found my dashboard that I wanted to redirect, did a web page search to locate the original WebMap ID, and replaced the ID with my new WebMap ID. (just FYI, the WebMap ID is located at the end of the URL when you are viewing your WebMap. It's the numeric code that's followed by "....webmap=")
Thanks to all who posted to help the greater GIS good!!!