i have done a few .
commen thing is the head to crack due to a blocked rad . they advise to change the rad or at least get it flow tested when they overheat .
the times i have seen them the temp gauge always stays on half way but the pressure in the expansion tank is massive . normally the crack between the valves so it will go down on 1 cylinder and smoke like buggery .
the job it's self is ok . take out drivers seat and floor pan and it is all very excessable . The worst part for me is taking off the propshaft that drives the aux belt and viscous fan .there isn't much room to swing it out of the way to get the crank pulley off . Also there is 1 hidden bolt under the thermostat housing to undo .