Road and Track

over the years, we have had only a few cars with this mount of bother, and I fully understand the owners' frustrations
Overheating can be very difficult to find, as the 'obvious" problems are not always the only ones. The various pressure and chemical tests for a blown/leaking head gasket are never perfect. if they find "no leaks" thats not 100% certainty. if they find a leak, then that's 100% (chemical reactions dont lie) 
You cant really compare a rebuild of an engine like a 3SGTE with a bolt-in second hand 2GR. different deal totally.
The biggest problem is the cost of labour and the man hours needed. In this country, any reputable mechanical shop charging less than about $90/hour is losing money. it  takes us about 40 hours to remove a 3SGTE, overhaul it fully (internal machining etc) and then put it back in. Add to that cost of parts and $7-$8K appears quickly. I doubt many others can do it this quickly as we are one of the only shops that do it all in-house, and have spent years building special tools,. jigs etc to do these cars. 
Generalist mechanics often look at these cars and run away and hide, because other jobs are much more profitable. They are not incompetent, they just dont want your work. Taking a MR2 to these people for major jobs like engine or transmission repairs is just asking for trouble as they get caught every time. Dealership can often be the worst, because 75% of their staff have no experience other than near-new cars, and these dont have any "old car" issues like i constantly see appear on these forums 
I hope this puts you all in the picture

 
Oh this is so well said !!!!!!!!!!!!!!!!!!!

I have spoken to terry a few times and he's a good guy. Doesn't piss in your pocket and knows his business with these engines. He also has a very promising gen 2 long block that might be making its way to Sydney for my car.

Gen 2? What happened to the 2GR

just beware, that you may fit this and you don't have a HG issue and it could be you cooling system, rad etc. as mandalay said, check the temp of the coolant hoses both off the head and the one pre thermostat to see if water is flowing thru rad back into the motor.

So check the hose pre thermostat from the radiator and check the hose from the coolant outlet assembly to the radiator?

Green = wrong. Most green **** contains silicates and borates which are bad for your water pump seals etc.  I had an argument with a Mazda dealer about this when my gf bought her Celica. anyway...
 
Use either Toyota 'long life coolant' (Red) or what I use is Nulon Red Long Life coolant which is an OAT based coolant.
 
If you do switch over to Red/OAT coolant (and you should) make you properly FLUSH the whole system out with water/rad flush first, as mixing the Red and green coolants apparently will sludge things up.
 
 
 

I think most will be fine. Mine had green in it but I can't remember if I used it or not. The one I had here was Techtaloy Flush I think.