Posted for "F. Barry Knotts" <bknotts@buckeye-express.com>:

I have a laser level (3 dimensional) and a Smart-Tool.  I use both on
the construction of the plane.  The Smart-Tool "module" is only about 8
inches long.  It also fits into a longer bar (24", 48" or 72") to make a
more traditional level in addition to angle finder.  See
http://www.speedpartz.com/smarttool.htm.  I bought my Smart-tool from
Vern at Lancair ($200) two years ago and the bar more recently.  The
speedpartz deal is the best I've seen.  And yes, you need this tool.