Probably depends upon the chosen authoring software. Common denominator would be each exported to a comma-delimited file, but not all software programs do it. If you were trying to combine files from different scanners no doubt you'd have to do the rearranging of at least some columns. IMHO hardly worth the effort. I use Win500 for speed of file reading/writing files to the scanner. I use ARC500 to additionally export data for wholesale search and replace, data merging and splitting, sharing, with a text editor (jedit.org) or spreadsheet (LibreOffice). HTH.
No, no mil or air except for the three approach-departure frequencies for McGuire AFB (KWRI). I am directly under the glideslope for the NE-SW long runway. Otherwise I am too far from any airports, even KWRI, to hear tower radios. Usual police, fire, EMS. I add the national railroad frequencies when traveling by train.
I'm assuming the scanner programming software can export data to a file with the file name extension CSV. jEdit and LibreOffice won't open proprietary formats (e.g., gr5, p500). Once opened as a CSV, you can muck around with the file with the software I mentioned. I would strongly suggest you save the original data file before exporting to CSV and give new file names to your experiments. The scanner programming software additionally has to have the capability of importing a CSV file for you to take advantage of the edits.
Just for jollies, I use data file names with dates. The last saved ARC500 was named 2010-02-15_v1. If I made changes to the file today, I would re-save it as 2010-03-04_v1 before making any changes. If I save multiple versions in a day, I'll bump the _v1 to _v2 (v=version). If I extract a subset of data, say, the railroad stuff, I'll name that file 2010-03-04_rr_v1 ... and so forth. This methodology works for me. Your mileage will vary. But the significant point remains clear: Back up your data file(s) before making changes.
Sorry, I don't know/use the '96 software that you use. But does this help?