If understand your problem correctly, I think you can use one-liner to solve it.

perl -pi.bak -e '/^2/ or substr $_, 99, 1, 9 and substr $_, 148, 1, "Z
+"' input_file_name
[download]

I might be wrong about the positions and the replacements but you can adjust that. The original file will be automatically copied to input_file_name.bak.