Nothing too clever I'm afraid....

Copy the chunk of image which has the swingarm in it onto a new layer.
Delete everything that isn't swingarm (eraser tool).
Ctrl-click the little layer preview window (gives an exact cutout marquee).
Create a new layer and use the paint can tool to fill the marquee with black.
Run the opacity slider down until you see the highlights come through.
Merge the two layers (still looks murky).
Use "Image/Adjustments/Brightness & Contrast" to tweak the highlights up.
Use "Save for web" so you can leave the layers open.

In this case it was easy because the require finish (satin) was the same as the alloy finish, so the highlights look the same.

You can use the same process to colour objects, just use a coloured fill not black. See attached nastiness....

And I'm definitely no expert! I learnt how to use ps many years back, and have kept all my bad habits since! :lol:

Cheers,

Ali

I always wondered how it was done, cheers:D

That last mock up is just gross:lol:lol