I bought the necessary Alternator and PS pump bracket kit from Kwik Performance. They also sell an A/C bracket kit: http://www.kwikperf.com/lsx_ac.html I haven't looked at the available crate engines, but IMHO I don't see why/how one would fit a Gen-2 better than another. I would recommend a "car" engine over a "truck" engine though. I started with truck-engine accessories and ended up changing to "car" engine accessories and belt spacing. (Different water pump, harmonic balancer and mounting brackets.) The car accessories make the engine almost 1 inch shorter (in front). I would avoid the "Corvette" accessories as they make things more compact than they need to be in a Gen-2. Most LS create engines do not include the computer/harness in the base price. GM Performance sells a kit with the Computer (programmed for performance), harness and electronic throttle module (drive by wire) for about $900. Drive-by wire has some advantages, but you will have to replace your gas pedal with an electronic gas pedal module. Not bad, just different.