Found my own solution, partly thanks to re-reading LindaP's solution from 8/22.
I'm not sure if I was doing something wrong, but if I just select from the first line of the header (where the page number is) down to the row of dashes above the first line of detail info on a page, it wasn't working because of all the blank lines above it, a total of 6 until it hit the detail on the previous page. The trick for me to get it to work was to include the 6 blank lines above the page number, and make the trap line = line 7.
Then the only remaining problem was that the first page wasn't being captured, so I used a text editor and added 6 blank lines. Not very elegant, but it worked.
At this point I assume that I wasn't doing something wrong, but the problem lay with my horrible medical billing program that places blank lines at the top of a printed report. Or was I doing something else wrong?