That is big work because you need to do it note by note, where in gp files that is already done by someone, and you only need to sync it or fix it a little. You don't actaually need guitar pro for importing in eof, but it is better if you can see it in some kind of editor where you can listen how it sound compared to the song, in eof you can't hear midi, you just see notes. Guitar pro files can be loaded in Tux Guitar, that is free, where you can also convert it to the other format of gp, especially from gp6 to gp5 or older, eof dont work with gp6 (gpx) files, and it is dumbed down version of guitar pro.