Converting Big Site To Wordpress?

Hi all,
A friend has a big site and it uses an old scrip. Now that script is old and dated, we want to convert it to wordpress but there are a lot of files/pages over 4000

How can we convert the site to wordpress but still keep all the urls the same or what is the easiest way to do this without losing rankings?

Cheers

 

What script is it using?

Despite the work involved if it really does have around 4000 files/pages converting to a Wordpress site would be very handy. It runs like 16%, supposedly, of the internet these days.

The Wordpress site has a list of Import Tools on its site which be of good use to your friend - http://codex.wordpress.org/Importing_Content

Otherwise, I would recommend paying someone that is competent in Wordpress and dealing with other scripts. This isn't exactly a hard exercise to do.

 

I ended up working it out
There are 4670 pages all added over about 5 years. Basically what I did was used an import tool called wp all import.
Imported the database then changed a few things so the images stayed in the same folder. Also changed the permalinks to suit the same
as the script because it had fileid and html in the url.

Took a half a bottle of Jack Daniels but I done it