Outer Limits 4x4 Board

hi guys, i have been having probs with my egt's, my patrol is a zd30 110000ks and is a 02 ser 3 manual, firstly what egt max should the car reach 5th gear flat on highway, ive only taken it to 550/600c but it would very quickly go over that, im sure it shouldnt be getting that high. possible air flow meter problem??
cheers
dave

where is the EGT probe fitted?

in the turbo dump pipe right after the turbo

plenty of info on grenades here
http://www.patrol4x4.com/forum/index.php