pdf as background image

hi, in a previous version of Pages I've added a PDF file as a background image (a letterhead), to retain the high quality text etc.

I've tried inserting the same PDF file into a new document but it won't allow me to move it to the back or backward... is this no longer possible? I've realised that the only way to do this is to make it a Master Object, but then there are two problems:

1. the image appears on every page (I only want it on the first); and
2. I now can't edit the text in front....

cheers

Ric