Before you comment, I know there are a few people out there who have already done the upgrade. I don't claim to be the first to do this but I am the first to write an instructable for it (I think).
You can also check out my new Bluetooth 5G iPod Video at iPodHackers.net
Let's get started!
NOTE: If you're looking for my instructable on how to add Internal Bluetooth capability to your iPod, click here
Step 1: What You Need
1) Unlike my other instructable where I showed How Do Upgrade Your iPod Mini With Flash Memory, you cannot simply replace the hard drive with a flash card. The 1.8" drive and CF interfaces are similar but you will need an adapter to bridge the interface from the card to the HD connector on the iPod.
I purchased the adapter for under $15 from an Asian vendor on eBay. It is not pretty but it works.
2) You will also need some cardboard and some hot melt glue or double sided foam tape.
3) iPod-Opening tools (non-marking plastic tools and/or flathead screwdriver.
5) Your iPod wall charger unit
5) Of course, you will need a fully ATA-Compliant Compact Flash card. Any size will work, but you can now get 8GB cards for under $70 as of this writing. I've had good luck with Transcend and Sandisk. Check the specs, not all cards will work.