I am back to work on my '66 standard microbus and was thinking
about the 6 to 12 volt conversion I plan to do.  A couple questions
came up.........
 I've read that I will have to grind a little aluminium
off the bell housing to get the 12 volt flywheel to fit and that I
will have to replace the starter bushing if I put in a 12 volt starter.
But, even if I do all that, I worry about things fitting if the
above mentioned center-line to center-line distance isn't the same.
 ------

the center is in the same place, but the 12V flywheel has a slightly larger
diameter.   

 
What will I have to do to make the fuel guage work when I do the
6 to 12 volt conversion?  
-------

nothing - just make sure it's hooked up right.  Id put it back together and
add gas to the tank before putting the motor in, just to make sure the sender
works.

and dont forget to change ALL your light bulbs, including dash light and
interior lights.  If you have anything but 12V5W bulbs in the interior lights
on a 12V system it melts the plastic covers.

:)