the rockschool one?
well its not that hard, it requires 3 songs. Two which must be one of there reportoires. The other one can be anything else. So pick a
Steve Vai song.
Theres also some a section called "technical excercises" which has loads of scales and other similar stuff where the examiner will ask you to play a few and in diffrent keys.
Theres also a QSP - Quick Study Peice - ITs like site reading, but you will be allowed about 20 mins to study it and then play it.
Then finally theres General Musicianship questions which is very easy - where they will ask you some theory and then guitar makes and amps etc. They might also ask you questions like What would you do if you broke your string on stage or something. Then just answer it like a guitarist not yourself. That way you will probably get the points.
One extra tip - Never use photocopies even the outside peice. The only photocopy that is allowed is only the outside peice that is
given to the examinier.