Moving Mambo

I have a Mambo test site in a subdirectory of an existing domain on DH. I need to create a new DH user and install the same (much modified) site into the new user’s space. Is there a simple way to do this? My plan is to do the following:
1.Back up the mySql DB.
2. Download the files from the test site (once approved)
3. Create new DH User.
4. Create new mySql DB for the new user
5. Import backed up mySql data
6. Upload original files.
I have a feeling this might not work as I would need to modify paths.

Another question: While I’m here there may be a better way to switch hosts.
The existing non-mambo site is on hosted by another outfit.
I plan to download the exisiting site and upload it to DH and then change domain name servers so to the user it looks like nothing has happened. Then install mambo into a subdirectory. Once it is working, then map the url to the mambo subdirectory. Any thoughts about a better way on that one?