First off, Welcome to the Forum.
Secondly, Here is what I suggest......You could purchase a Carver product called the DPL-33 Surround Sound Processor for not alot of $$$. I suggest that you look here for it at www.vintagehifipgh.com
The owner of the store Tom (beemers417) is a fellow Forum Member here and I know that has at least 1 or 2 in stock that are in perfect shape for sale.
As far as hooking it up....its really a piece of cake. You will use your existing Carver Receiver to power your left and right channels and the DPL-33 will power your center channel and rear surrounds. There all also provisions on the back of it as well if you were to add a subwoofer with selective crossover settings for convenience sake.
The DPL-33 is a real gem.You will accomplish goal of surround sound, you get to keep your existing Carver receiver, and all for very little money.
Take Care And I Hope That You Decide To Stick Around Here With Us On The Carver Forum.-----BILL(BB3)
Carver Gear : C-9, C-16, C-19, 4-TFM55's, 2-TFM35's, 1-TFM25, 2-Silver 7-T's, 490T.
Non Carver Gear : Anthem AVM50V, Anthem Pre2L, Sonic Frontiers SFCD-1, Denon DCD1560, Panasonic DMK23, Sony BDP-S350, Sony PS3, Sony 52" XBR-6, Sony 32" XBR-6, Nintendo Wii
Speakers : Polk Audio : SDA-SRS, SDA-SRS 1.2TL, SDA-CRS+, RTA-15TL, 3- Velodyne F-1500's