Is it safe to assume the data source returns a floating point number of 0.0 to 10.0 vdc?
In any case, on the Data Scaling for "Data From:" put whatever number represents zero volts, and in "Data To:" put the value that represents ten volts.
In "Display From:" put whatever number of pounds is the same as zero volts (perhaps zero?) and in "Display To:" put the number of pounds that is indicated by ten volts.
You may also need to choose Scale to Floating point in the drop down list above these four values. I would also go ahead and populate the format tab of the tag with a meaningful Label, and choose a Format Type of Numeric, then put a Units label of " pounds" or " lbs".
I like to put a single space at the beginning of my units for most tags so that they're more readable than running right up against the numeric value.
Now with all that done, you can drag and drop your tag on a screen and it should look nice "out of the box". Note that dragging and dropping tags is done by picking them from the resource pane on the right.
Also be aware that the scaling values do not have to be constants. They could be other tags or internal tags that you can edit at run time. If you use internal tags for scaling, be sure and make them retentive so they will be maintained after you adjust them.