Can anyone recommend a link to a source for a "simple" crosswalk for the Paper Copy of Institutional claims to the 837I, field-by-field?

In essence, I would like a general knowledge of which data on the hard copy claim (HCFA-1450/UB-04) goes onto the 837I format.

There is particular interst in knowing if there are any fields, or data elements, omitted through this process, or will the 837I only enhance the amount of information that is submitted?

Any assistance would be greatly appreciated.