moving register.php and userlist.php outside of punbb

So I would like to remove register.php and userlist.php outside of punbb to create a better integrated site.

Now moving the files out of the punbb directory is easy...I simply move them and then change the pun_root define and path to common.php and then run them and they seem to operate as before with little change.

However I want to remove the header.php include (or at least the main.tpl influence over these files) from both files and when I do that and refresh then I am presented with a blank screen.

How would I go about ridding register.php and userlist.php of their ties to main.tpl?

Thanks in advance