Convert PS from A4 portrait to A4 Landscape

Hi All
I have a program that generates a complex report designed for an A3 page (but actually printed on an A4 page and then enlarged in a photocopier because I don't have an A3 printer!) .

It accesses data from a database and generates a file of postscript commands (mostly co-ordinates and text) that are then converted (Adobe Distiller) into a pdf file which is then circulated and/or printed.

The report maybe a single page or multiple pages depending on how many years (1/page) of data are being printed. Each page has around 700 items (actually names of people in a competition)

I now have a requirement to produce the single A3 page as 2 * A4 pages so that the 2 * A4 pages can be viewed as a single A3 when bound into a book faing each other. The easiest way seems to be to

Create the .ps file for the top half

Rotate it 90 degrees

Scale it by 1.414 (X & Y)

Showpage

Create the .ps file for the bottom half

Rotate it 90 degrees

Scale it by 1.414 (X & Y)

Showpage

And then onto the next year and so on.

So as a test, I tried adding 90 Rotate at the beginning of the .ps file (just before the first command to add text) and just got a blank page. Tried at the end of the file which did nothing. So I clearly do not understand how this is supposed to wrok

Please, what is the best way to achieve this objective  (a ps file for A4 portrait -> 2*A4 landscape rotated and scaled up) for multiple years

Thanks for any suggestions.