well here's a list of what i've done:
remove "guts" from thermostat. still no difference, just takes longer to warm up in morning.
remove intercooler that was just sitting there, still did nothing, as expected (think of all the cars running stock radiator, with a FMIC, maybe even an aircon and trans fluid cooler infront of them that don't overheat).
reverse flush block (before the rad went back into the ute, didn't really get anything out of it, except a waste of good coolant)

the thermo's are pretty good i've found, mainly around town. If they cut in the water temp drops almost instantly about 5degC. out on the open road they are fairly ineffective.

the rad isnt that big, measures about 12"high x 21"wide x 1.5" thick approx.

i think i've done a head gasket.
did i mention in this thread that i put a new water pump on not too long ago? so that rules bas circulation out.