Kidace, Sim will no doubt reply in greater detail. But I'll try and help as you've got time constraints. What I think needs to be done is as follows (it's a 1:1 process):

1/
Go to the QUICKSTART GUIDE section of the electronic docs in the HTML folder. Then follow the instructions: How to record a disk image. That will get you the GI file.

2/
Thereafter as per the ps2ownz tutorial.