This definitely seems like an odd set up. Summary Fields are fully visible in browse mode with Filemaker 7 and even earlier versions.
Sub-Summary layout parts--which are often used to display summary fields--are not visible in browse mode for all versions except filemaker 10.
Needing a special page size just view the data, seems very extreme, You might find that a restructuring of your tables would reduce the number of columns needed for you report. You can also set up several layouts--each of which prints a subset of the fields.
You can of course print in landscape orienation to legal size paper to squeeze a few extra inches of data on your report as well.