Distance inquiry- need to "measure" a distance

[cfee]

I need to measure the absolute distance between a curve and a seperate planar surface (or possibly 2 planar surfaces). As coordinate points seem unavailable and absolute locations on a feature are difficult to distinguish, I don't trust "true" and "apparent" value returns. Any suggestions? The abilility to take detailed measurements is critical to good design, but short of setting up a draft environment and "dimensioning" the feature, I'm stuck. Thanks- Cfee