good to hear, what brand was the water pump and timing belt?

So are you saying the water pump was actually branded as Repco ?
You have been very fortunate not to have a disaster on your hands.
Also great to have a knowledgeable mechanic to do the job !

Alright so all has not been well since the last update, we tested the car around the roads around the workshop and all seemed fine, my mechanic then drove it home for me. However, pulling onto the freeway there was an explosion of coolant behind his head :(. The head cylinder head was badly warped and compressed air had made its way into the cooling system and got bad enough that it blew the top hose off the radiator cap and emptied itself on the side of the road. My legendary mechanic arranged to have it towed back to the workshop where he tore it all down to see what was what and we found that the cylinders 2 and 3 were full of coolant.
 

 
The head gasket was fine but there was a massive warp in the middle of the head. Mechanic has a mill so he put the head on it and took cuts before it was all flat and brand new again. It looks so damn pretty!
 

 
There was alot taken off but thank god its still a non-interference engine. I can now happily report that the car has been running reliably ever since. The suspension and steering rack upgrades we did while the car was on the hoist have made a massive difference, there are no more clunks and bumps the car drives like new! I haven't driven it in anger yet because it's still only been a week but I can already notice the increased compression has made the car more responsive and is a pleasure to drive.
 
Now I can get back to the more cosmetic mods. My mate has a 3D printer and those invested in the thread or know the car will know I'm holing my boost controller in the ash tray bit with foam from the pack it came in. I got my mate to 3D print me a mount and it look so great. I'll sand it with a dremel after we move to Sydney and wrap it in some CF wrap to match the rest of the trim.
 

 
 

I like the 3d print astray holder thingo, good thinking.

Alright so once again all is not well in camp MR2, I took the car for a lengthy drive to newcastle the other day and it was fine the entire way right up until the moment when I turned the car off, I momentarily turned the ignition back on to check gauges and this is what came up:

 
Something was clearly wrong as it had only gone up while the car was off. The same thing happened the other day when it was 40+ degrees, I took the car out to fill up with fuel and I noticed the gauge slightly climbing, pulled over and turned it off and same thing happened. The car will probably need a new radiator, so any suggestions? I've heard good things about Mishimoto and PWR.

Are you sure your coolant system is bleed properly.