Sounds like fun. Reminds me of hte old days with Run DMC and Aerosmith. But combining the two is a really artsy type of thing, albeit on a small scale.
Now to the subtopic which tomb brought up and got called out on. ANYBODY with a high degree in music will be quick to point out the faults in your arguments. Most notably, Bobby Mcferrin, who just so happens to be one of the most prolific music instructors right here in San Francisco. A good piece of hip-hop, he said, will take about a week to compose and partially master. The rest is up to the individual artist as to the direction he/she wants to take with the base song. I'd go further in my notes to add to what I've got pertaining to that day (10-24-1998, that's when I got to use my first synthesizer ^_^), but I know I'll run out of room due to the character limit.
Back on topic. As I said, it's a fun project to undertake. Keep us up to date through your news posts ^_^.