My 2004 Ford Mustang convertible 40th anniversary edition

I’m new to this so please bear with me.

I have a 2004 Ford Mustang convertible’s 40th anniversary edition it’s in the shop today getting New rack and Pinion installed my question is after that’s installed and the front in alignment is done well I notice any difference in the driving I was told that it should start making that weird noise that it makes and that I should notice then I will have better control of the steering.
Other question I was also told that my car is one of 5,700 made, Is that also true.?
I was always a Trans Am kind a guy until I got this mustang back On October 1, 2015 it was the best $8000 I could ever spend. I’m including a Photo

There’s a couple mistakes in the post I made I was told after the new rack and Pinion was installed That that weird sound I was hearing Will stop Is that true? Also I’m showing you a before and after picture of all the work I’ve done on it so far and needed your opinion on it thank you for any help

Thank you. it has 120,500 I keep it very clean and maintained.