if you run the auto all you need to do is shorten the driveshaft and either modify the existing transmission crossmember, or make a new one to fit the longer transmission.. if you are runnung the original shifter you will need to replace the gate in the mechanism, it cost about 25 bucks and is available from
www.bowtieoverdrives.com
the manual swap is alittle more time end money consuming but not much, you will need a new pedal setup and a hydraulic mastercylinder for the clutch, the t56 that comes with a camaro engine wont withstand 600 hp for long periods of time and neither will the clutch, but weather you get a centerforce, mcleod street twin or tilton carbon/carbon multidisc clutch is very much a question of money and preference as they are 500, 1200 and 3500 USD respectively..
i would go with a 4l60e and mount a
http://www.twistmachine.com/ shifter... which is what im actually going to do my self...