I have an 01 DBW with the stock cruise stalk on the column. It's the same on all 99-07 gen 3 engines with the only difference being if the engine is DBC has a servo box you also have to mount. Mostly it is just hooking up wires. An 84+ G body has the correct open/closed circuit wiring, pre 84 stuff either put a newer stalk in or you have to do some non factory wiring as far as what hooks up to where. Only issue I had was the PCM looks for 4 ohms over the taillight circuit to prove the "off" signal is present, if you have less than 3.2ish ohms the PCM will think the tail lights arent working which won't give the PCM the signal it needs to turn cruise off so it defaults to not working.
But yeah, if you are E rod or gen 4 LS cruise is all routed through the BCM, although E rod MIGHT be easier since they know it's for swaps.