02 into 06
Should go right in, both are small block motors. Only real difference is the top end. Parts fische says the pipes are even the same. It even says the 04-07 500 cdi was used on the 04 and 05 600 so you won't have to change that. 06 and 07 600 DCI was different and I think that was because they went to DET.
You will need to switch the 500 flywheel to the 600 and I would use that pull starter too. 02 600 didn't have Perc and the degree on the flywheel is different. Also the pull starter dog is different on a Perc motor.
Other than those 2 things it should be simply pull one and drop the other in.
Clutch spring on 500 is black green, 600 straight black. Weights on the 500 were 10-56 on the 600 10-58 so you may need to make a change there. More power, more weight.
Carb jetting, I would run what you have in the 500 although initially you may want a little richer main say 2 steps then work down. The 600 had larger mains but leaner pilot, needle and stater jet. Polaris went larger on those in the 06 with a smaller main in order to get better fuel economy. The 600 will probably run fine with your 500 calibration but fatten the top up just to play it safe to start. Hang onto your 500 mains and you probably will end up using them.