Evening guys (and girls, if there are any reading this?) can anyone with a better understanding of Photoshop do a colour change on my Monte for me?

the colour/s in question are 

3M gloss kiwi

3M gloss mandarin

everytime I try I seem to change or do something strange to the black, I'm leaning towards the green, opinions please. The wife says the car's "already in your face" but not enough for my liking. Thanks in advance

 

I tend to isolate the area - either by using magic wand tool or by duplicating the image into a new layer and deleting everything but the bits i want to change the colour of - and then just play with the colour curves accordingly

 

only spent 30 seconds on these hence the orange being ok but the green turning into a lime green chrome - be fun if you could get it

 

 

Thanks Pasty, now the lime green chrome?? maybe a bit over the top