C#.net subtract value from string using a regular expression

I'm using the regular expression shown below to find a given string in a text file.  That parts works.  The problem is that I need to subtract 7 from the number in that string in the file.  My code below is currently just writing SE*[d-[7]]*0001~ to the text file instead of updating it.  That makes sense since I put that in the replace portion of the command, but I don't know how to make this work otherwise.  Any ideas?

File.WriteAllText(
                  file,
                  Regex.Replace(File.ReadAllText(file), @"SE\*\d+\*0001~", "SE*[d-[7]]*0001~", RegexOptions.Multiline)
                );

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Here is an example of the string I need to subtract 7 from:

SE*2078*0001~

I need it to say:

 SE*2071*0001~