Putting this here because I didn't find the guides on the web that useful. This is for the right hand drive manual Japanese/Australian style dash board removal but should translate backwards for the US style and be fairly easy with the automatic gear lever. It's a big job, but if you know what to expect then it should be fairly quick. Removal of the dash is necessary if you want to change the air conditioning evaporator, blower box or heater. It's also useful just to do general wiring work.
 
1. Disconnect battery. Cables flapping in the breeze will short out and blow fuses.
 
2. Remove A pillar plastics, stereo surround, stereo and it's brackets, rear box (the thing that sits between the driver and passenger at the back of the cabin), gear shifter knob, gear shifter surround, centre section (the bit the gear stick goes through), glove box, instrument cluster, lever surround and various other bits of plastic attached to the dash until you are left with just the dash in place.
 
This is where it gets tricky and if you don't do it right you could break something or it'll just be impossible to remove or put back.
 
3. Remove steering wheel and indicator lever stalk (just let the levers hang down on their wiring). Tilt the steering column at it's lowest position. Put in reverse and have the handbrake on with the lever up as high as it will go. Note: for steering wheel removal you will need torx driver for an airbag wheel.
 
Now you can actually remove or replace the dash.
 
4. Two bolts on the left side, one is under the little vent which pops out. Three bolts and a nut on the right side.
 
5. Pull the right side (driver) out first then the passenger side, remove through the driver's door. Note: this should be reversed for US vehicles.
 
6. Disconnect the clock and the light sensor (if it has one)
 
To install do the reverse, slide it through the driver's door, then slide the passenger side in first, then the driver's side. Make sure you get it over the tilt lever, and also make sure the heater air piping lines up properly. Be careful not to scrape up your handbrake lever or tilt lever. Also don't forget to keep track of where all the screws and bolts come from. Put them in zip lock bags or what not.

Just a note as I am just going through this now, you should only need to remove the glovebox to remove the evaporator and blower
You will need to remove dash if you need access to the heater core which was my problem
I will be putting mine back in tonight all going well so will update if it is possible to do evaporator with dash in place

I tried removing the evaporator with dash in place and it had some bolts way up out of reach of any tool I had... you might have better success. When I did my Paseo (which is very similar in parts it's like a mini version of the MR2) I could remove the evaporator while the dash was in place that's why I thought I'd give it a go.

Ok fingers crossed as iam putting my faulty evaporator back in for now as I cannot get a new one easily

How is it faulty? I got my local guy to get me one for $220. He said it was the last in the country though. The evaporators on ebay from America don't fit, they are around the wrong way.

I pulled it all out to replace my leaking heater core and refurb all the seals on the blower unit
The evaporator has a bit of corrosion in one spot and looks like the green uv dye I have in my system is seeping out, I just wanted to replace it as a precaution
I also got one of the US ones not knowing they would be reversed so I am out of pocket on that one and cannot currently afford to pay another $220
I just need to get it all back together for engineering my engine swap and worry about it later

If you have green dye on your evaporator it's most likely the o rings on the TX valve and the pressure switch (which uses a small one). Might be worth changing them in the future before you gas it up.