With the preamp OUT feeding the FX unit IN, I think you can get what you need by using a "Y" connector on the FX unit OUT. One side of the Y goes to your recorder IN, and the other one goes to the power amp IN.

If you want to record "silently" (those 03:00 AM sessions can just ruin your neighbor's attitude!), disconnect the feed to the power amp. You can monitor from your recorder with headphones.