Re: Replace Shocks 05 V
I'm assuming the dealer-installed Performance Shock Package means you have the FG2 dampers. (I didn't realize that was a dealer option, but whatever.) You can verify which you have by looking to see if the big yellow stickers on the dampers have a dashed black border on them. See the Cadillac FAQ for pictures of what you're looking for.
So, if you do have FG2s, you can get FE4s (the "stock" suspension) to replace them. That link I posted has the part numbers, so you can shop prices on Amazon, Rockauto.com, etc. Also give Luke @ Lindsay a call, he generally has very good pricing.
Here are some used FE4s for sale in the Classifieds. Might be able to get those for cheap.
'05 Stealth Grey CTS-V, 19x8.5/10" CCW T140s with Toyo Proxes T1 Sports (summer), black Team Dynamics ProRace 1.2 wheels with 275/35-18 R-compounds (track), Hyperblack Rota Torques (winter), KW Variant3s, V2 front brakes, Hotchkis rear sway bar, EPS cam, TEA-ported 243 heads, FAST92 intake w/LS2 TB, JBA Camaro/G8 1-3/4" shorty headers w/JBA cat pipes, Corsa exhaust, UUC motor and tranny mounts, UUC shifter, MAPerformance trailing arms, Specter cradle bushings, etc...