I have had the exact same issue and changed the voltage reg from another dash to fix the problem.
 
It is an easy swap if you have a spare dash to rob for the part.
 
 

• Turn heater and wiper switches to middle position so they are pointing straight out.
  
• Undo threaded rings on wiper and heater switches (straight cir clip pliers work well for this)
  
• Undo philips screw ontop of dash (early model dash)
  
• Dash should pull out a little bit now, but dont pull anything just yet.
  
• Reach under dash and unscrew the fitting on the end of your speedo cable (should be a collar on end of cable and should be able to unwind by hand)
  
• From memory this should allow you to pull the dash out a little further so you can unplug the big round wiring harness plug.
  
• Dash should come out now.
  
• Undo philips screw that is holding voltage reg down and carefully pull voltage reg off.
  

Assembly is reverse order of the above process.
 
I haven't done late model dash before, but would think same process applies.
 
Also I hope I havnt missed any steps as im going from memory of when i did mine... so take your time and dont force anything.
 
Hope this helps you out.

I agree with you about the 1000 dash being ordinary.
Coupe has a good dash.
 
Id go so far as to say id like a coupe dash in my sedan.
 
 
Ill throw this in for some inspiration on custom building... 
Years ago my brother made a custom dash for his Hilux, He used speedhut gauges, LED lights for indicator/warning lights and made up a sticker to label it all.
 
Some of the LED lights needed resistors wired up in an arrangement called a "voltage divider"  to reduce their brightness as well.
 
Link to a pic of his old Hilux dash...
http://www.retrojdm.com/Images/GalleryPhotos/Original/2010-04-21%2002.jpg
 
Im looking foward to seeing what you cook up in the dash department.

Hilux dash is smart and modern looking. I have only  ordered standard looking 2" gauges myself, and I wondered about LED brightness actually since a bright high beam indicator light at night would be irritating. The 1k only needs three bulbs: indicators and high beam. Since LEDs are quite finicky I also thought something  as simple as  a resistor in series probably wouldn't work

I might be out on my own including a my buddy but we prefer
the b10 dash for the b10 or vb10 or b20..
This is from a designers point of view as the original dash mates
well to the rest or overall lines much like an old retro radio.
My buddy even got a tacho from a valiant that rises in revs
just like the original left to right which suited it very well.
That and the horizontal old style air con all look very factory.
I would repair what is required but use as mentioned some
kind of better lighting etc.
The hilux dash looks great but the Miata original ones are
also amazing for that refined yet retro finish.

early dash and guage cluster for the win not that foam flimsy thing!
that red Mazda Roaster would look mad with a red interior cream or white duco sedan