2 core versus 3 core radiators

[Bigcol]

right oh........
time for an update on my over heating (again, apologies to Bloodyaussie)

factory dash gauge - sits on just below half (about 85* off a 90* angle)
Autron Temp gauge - sits on 95* - to 110* (alarm goes off at 115*)
engine bay Temp (Autron) was sitting on 72*
EGTs 300* - Autron
Boost 8lb -Autron
sitting on 95kms

slight hill / gradual rise -
temp alarm goes off
factory gauge goes just past half way ( to about 92* off a 90* angle)
air con goes off
boost spikes to 12lb
EGT goes to 550*

radiator was replaced with new Nissan rad Xmas 2011
rad was flushed Xmas 2013
using factory coolant

is it my rad........????
is it my thermostat..........?????
is it my water pump.........?????
is it my Viscus fan...........?????
is it the fan itself.............????
is it a shit heap because the air con goes off when its a 43* day...........YES..............

I welcome your suggestions...........

went to Joondalup 4x4 yesterday for them to have a look at what could possibly be wrong
well now........

is it my rad........remember, it was flushed Xmas 2013 - they took it out and back flushed it - lots of scale I was told.........
is it my thermostat..........old thermostat marked at 85* - didnt open untill 92* and never fully opened even at 110* - temp probe in water bench test - new thermostat put in
is it my water pump.........was an after market brand, compared to new Nissan one - slightly larger fins on the impellor from Mr Nissan
is it my Viscus fan...........was not working properly - pulled apart, small valve for oil movement was "jammed / stuck" shut- replaced with new anyway
is it the fan itself.............one small-ish crack, apart from that and dirty - looked ok

while the radiator was out, they also blew the Aircon rad out (from engine side) was lots and lots of dust and dirt and leaves came out

now have to hook up the Van and go for a drive to see if it is alot better, hopefully this weekend go for a drive and find out

again, sorry for the highjack Bloodyaussie