The Larry Wiliams' indicator named WillSpread isquite easy to plot in MetaStock for Windows version 6.5.
Using version 6.5 of MetaStock for Windows, please follow these steps.

Plot the underlying commodity.
Drag the Spread Indicator from the indicator quicklist to this commodity chart.
Select either Tbonds or Tbills as the security touse to spread. I recommend you plot this in a new inner window.
Drag the Price Oscillator from the indicator quicklist and drop it on the SPREAD plot, not the price plot. The parameters Mr. Williams' uses are 7 and 11 time period exponential moving averages.You also want to use "points" as the method. This plot is the WillSpreadindicator.
At this point, you may change the Spread Indicatorplot's color to match the background of the chart, or perhaps move the WillSpread indicator to a separate inner window.
If you save this first effort as a template, perhapsnamed WillSpread, you are able to apply this template to any commodity you wish and the indicator will be automatically calculated against that commodity. You may also use the "Next Security" functionwithin MetaStock for Windows to view each of your commodities by setting the options for next security to "Keep line studies". If you apply this template to the first commodity in your futures folder, you may then use the right arrow to move down the folder contents.
Each new commodity will have the WillSpread calculated as it is loaded.