c# – Using Regex to skip a word in a string along with special character

I have a string as:

string str = "= Fields!Change_Date.Value & Fields!Change_User.Value";

I want the output as:

Change_Date && Change_User

I am able to achieve it but after using multiple replace methods as:

string str = "= Fields!Change_Date.Value & Fields!Change_User.Value";
        
string x = Regex.Replace(str, @"=? Fields!", " ");            
string y = Regex.Replace(x, @".Value", "");
string z = Regex.Replace(y, @"&", "&&");

How Can I achieve this at one go. Is that possible?