There is a generic replacement of radiators for free on the internet at: http://www.2carpros.com/how_to/how_to_replace_radiator.htm
It has color pictures with arrows on exactly how to replace a radiator. I did this a few years ago with a VW and it is not an easy job as moving the radiator is not an easy task.
If you want specific instructions then you will probably have to go to Chilton to do it. It is a great resource for do it yourself people. The website is: http://www.autorepairmanuals.biz/site/573683/page/281111/site?OVRAW=Chilton%201999%20Saab%209-5&OVKEY=saab%209%205%20repair%20manual&OVMTC=advanced&OVADID=1857880522&OVKWID=49121971022
Good luck with the replacement.