ORIGINAL: Diver944
One thing, The dye put in to the AC refrigerant will go nowhere near the coolant in your expansion tank, they are seperate systems. You probably mean the green colour of your particular antifreeze in the coolant.
I assumed it was antifreeze replaced because the rad has to come out to get to the condenser. I just took mine out on Sunday and I don't think it would come out with the rad in place. I replaced the one in the Pug the week before and it's the same.