03 grand vitara egr valve removal.

i agreed to replace an egr valve for a friend for some extra money. ive found a couple sites where people have removed the intake manifold to access the egr valve easier. i was wondering if anyone has done this without removing the intake and how difficult was it? also if anyone may know what size bolts hold that in. they appear to be 12mm but the more info i can get prior to saturday afternoon the better. thanks for any help.