Deanyel, when you mentioned there should be play in the linkage to allow the throttle to return to the closed position you reminded me of something.

When looking down into the throttle body the butterfly valve never closes fully, regardless of if the vehicle is running or not. I would roughly estimate when it comes to a rest (or closed position) the valve is sitting so the leading edge (the edge facing the front of the vehicle) is cocked upwards showing a gap of no more than a millimeter or two. Is this normal operation?

Also, in terms of the linkage, I have read somewhere (not sure where as I have been going through a bunch of posts on several boards) that the cable should be tight with just a little bit of give. Mine was not and I used the black thumb wheel on the linkage to tighten the cable. However when I started the car the idle jumped up to around 1200 rpms so I loosened it back up again by a few turns and the idle returned to normal.

Like I said earlier I'm posting everything I think of to paint the clearest picture I can of what I am experiencing. Thanks again for everybody's help!