ReWire is your friend, go look up the proceedure for using Reason as a ReWire slave to Logic.
I used to use Reason 3 with Protools and Logic, but haven't done so for a while, hence the lack of detail, but ReWire will stream a number of discrete audio tracks directly into the Logic mixer.
You have to launch Logic and then Reason, and make some changes to the Reason set-up, but I can't remember the details.