Wordpress Permalinks and Drupal

I'm currently in the process of converting my Wordpress site to Drupal, but because a lot of the data has been restructured and needs to be both edited and reclassified, I'm NOT using an automated system. Instead I'm entering the new data manually so that I can edit and reclassify everything correctly as I go.

I'm having a problem with Wordpress's permalinks though. I never used clean URLs for my Wordpress site, but I want to use them for Drupal of course. How do I do that without breaking all external links to the site's content?

Basically, the permalinks now look like this "example.com/?p=7". How do a setup a redirect for that to a Drupal clean URL? I'm using URL aliasing, URL redirects and Global Redirects, but can't seem to get it to work. I'm not sure if I'm doing this incorrectly, or misinterpreting something, but just setting up a redirect doesn't work. I can create one that looks right, but when I then go to "example.com/?p=7" I am not redirected appropriately.

I've done some searching on the Drupal site, but haven't found much yet. Is there another module I need?

Thank you all for your time and effort in advance. Your help is greatly appreciated.

Dave