thanx to Freeplay who updated his fileassistant i can now easily explain it in a way easier way. Note this is not the last release as i plan on making an automated one soon.
1.axtract all of birdmans font pack to anywhere on you memory stick (make sure it unzipped and you at least have about 30mb of unused space)
2. go into fileassistant, press circle over birdmans fontpack, circle over psp fonts, choose which one you want (press circle over it), press circle on fontmod.
3. now on either the left or right section of the program... whichever one says ms0:/ on the top click fontmod(circle) which shold have already been there cause you should have it there from the last pack.
4. go to the other box (side) and go over the ltn0.pgf and press L till you see copy in red and then press the right trigger.
5 it says copy OK than hit home and Viola your done.
AIM is iizstupidandsoru