In your example, you have:

$_ =~ s/(.{10})(.{4})(.{6})(.{6})/$3$2$4$1/g;

I understand your regex pattern, but I'm concerned about the second part. Would there be a way to make this dynamic? For instance, putting in a string based on what I read in from the config file? (let's say the config file wants $3 as the first parameter, then $2 as the second parameter, then the result of some function with $4 as input into that function as the third parameter, etc...).

Sorry if it seems like I'm useless. :) Perl isn't my first language, and it has been hard adjusting to the new syntax.