It was a very good idea to use the milkfrotter source as a phonecord. It fits perfect for that.

Now dont take this personal but as a learning possibility please, the cutout of the phone is really badly done, this is because, im guessing you have used the magic wand, since it has a white background, but you have cut the shadow that the author of your phone source had on his picture also, and that shadow just doesnt fit with your adjustions.I suggest you go back to your phone source and cut it out again using the pentool this time and leaving out the shadows this time. Then you can apply all the other stuff you have done. And be aware of the light reflections, they should not be as bright on rusty old metal as on plastic, as Im guessing its plastic and not the real old material the phones used to be made of back in the days.

The shadowing that you have added yourself look ok to me. but you do need to tone down the lightreflections because they dont work compared to the softer shading and the old metal.

I like it, very nice chop for me

Great idea!..