Duplicate PERWEIGHTUNIT Module

[Bread_O]

Can someone explain to me how to duplicate the perweightunit shipping module.

I have found the two files in the includes/languages/modules/shipping and includes/modules/shipping.

I know I have to duplicate and rename to new files

What do I need to change in these files to duplicate the module?

Urgent please

Thanks

[Ajeh]

Copy the two files:
/includes/modules/shipping/perweightunit.php
/includes/languages/english/modules/shipping/perweightunit.php

to new files, say you call the next set perweightunit2
/includes/modules/shipping/perweightunit2.php
/includes/languages/english/modules/shipping/perweightunit2.php

Now change all:
perweightunit

to read:
perweightunit2

And change all:
PERWEIGHTUNIT

to read:
PERWEIGHTUNIT2

These are case sensative ...