so you have a new headgasket, new radiator hoses, and the fan is hot wired so it stays on all the time
when he was driving it, it was not over heating
i will just name of couple of things for you to consider:
thermastat
was the cooling system burped after installation
did you also replace the water pump
did you check the head to see if it was warped since you replaced the headgasket
did you overfill the overflow tank
__________________
if you can only race me in a straight line then whats the point 
...91 SMF SCCA
http://www.flickr.com/photos/8341770@N07/5601083432/http://www.flickr.com/photos/8341770@N07/5601083432/ by http://www.flickr.com/people/8341770@N07/, on Flickr
I see people out there spending money on the car to improve it … If you spend half that effort just working on your driving skills, making you and the car work together as a team, then you’ll go faster – period. To make the car go a second faster on the track takes a lot more energy and money than making yourself drive it one second faster.
– the late Tom Thrash SCCA Solo E Production