I went to look for bulbs for the as mentioned above, I see a LED replacement... Is that sacrilege or can they be embraced? The same LED story, uses less power, less heat and better light emitting qualities... Durable it sez..
I'm not able to cut and paste the company.. so heres their local. superbrightLED.com.. 
Sneezles61

LED lights require D/C current and your instrument lights are on A/C current. I guess the easy way would be installing a Vape 12 Volt D/C mag kit to do this.

Embrace the vintage enduro....leave it 6 volt and buy the correct 3 Watt bulbs. I've always been able to find what I need on Ebay.

Well, I wasn't fighting the "usual" scenario... Now I have more stuff too study up on...  volt AC...  
Am I suppose to say thanks or Dag Gummit?
Sneezles61

Well, I'm trying to get an understanding.. Why would Yamaha utilize AC for instruments and headlight and not put a bigger full wave rectifier in  and run all its lights on a DC.. They did only for the ignition and battery charging side..  
Maybe using a rectifier wasn't as reliable way back then? It couldn't have added any perceivable weight to the bike... 
Perhaps its just wrong.. but I'm going to experiment with this stuff before I put the tank back on and get my bike out the door for riding enjoyment.. I hope there is some electric guru out there can shed the light.. 
Sneezles61

Interesting! I remember putting LED bulbs in my stock 250A tach and speedo years ago. I just checked to make sure and yep, their still there. I bought them from Superbright. I have one in the high beam indicator, tach and speedo each have one for the back lighting. I do have one "standard" bulb in the turn signal indicator? The led work great no problems, I like them. I think I'll buy some more so I'll have one for the turn signal indicator.

In my experience, as long as the polarity is correct, you can use an LED bulb.

Lotsa reading this AM... I'm getting a little more understanding as to why... 
And yes LED lights can work.. and they are to be wired with polarity in mind... I've read that even as little as 3 volts will make a LED (small ones) glow.. 
 The issue I'm trying to solve... my bike was ran without a working head light and lights are fried... I'm sorting out the wiring.. And the way the battery works in the system as a whole...
I believe I have a handle on repairing some stuff and what wires make it tick... correctly.. Now.. out to the garage for some adventure... 
I've gotta make a make-shift temp gas tank to check the wires are correct when the bike is running.. I'll be very happy to verify that and put the tank on.. Oh yeah... order up a box of lights bulbs too!
Sneezles61 

There's a reason you don't have one in your turn signal indicator.  Bulb switches polarity from left to right.  

Some LED's are no longer polarity sensitive so can work...  technology has improved.

Nope, the LED bulb works fine in the turn signal indicator. I was curious as to why I didn't have one there so I switched bulbs, works fine. I guess I didn't buy enough to switch all.