Yes no way to cross family. I could allow it, its my codes choice to not, but it seems really risky and the underlying hardware is different (this is how I partition the family codes by actual hardware in the firmware).
Restore may bypass that check so you could try if you really wanted a brick. If it gives same family check code I could add a checkbox to allow you to try
I really dont want to control what people do but this would be a pretty high chance of brick imo. The rest I have always felt self on (even when others insisted not too) as the hardware is identical.