DangerRanger85

Ok i blew my 3.8 up found a motor and trans out of a tahoe full harness pcm and all for engine and tranny control.I have heard i will need and ls1 cross member is this true and my concern is the instrument cluster speedo tack ect.Really i need help on all of the wiring that needs to be done i have no problem with a standalone for the engine tranny. But as far as the speedo and all goes can anyone give me any advice has anyone done this swap and can tell me what im getting myself into because i have went into swaps blind before and don't much care for it.