YaBB to phpBB conversion

I have a YaBB board (that has some mods added to it, what those mods are, I forget) and I need data from the yabb board converted to phpBB. So I need a converter to convert all my users and all information associated with them over to the new forum. The users' information is the only thing I need brought over. I know there is a currently a script out there, but it wont work for this one because of the mods that I have. I will provide the programmer with the different files that they will be dealing with so they can create the script. It doesn't need to be fancy or have some high tech looking interface, it just needs to work, work correctly, and not screw anything up. :) I will be making a quick decision. Best price and turnaround time will most likely win the job