you tube had a live feed over weekend showing diamond replacement in Fostoria. it showed a lot of the big and small types of work needed on a major project like this. someone might have a timelaps on this
I saw a video, believe it was this project. A link someone sent of work done, on YouTube. Wish I could find that again.
Thankfully I think F Tower still stands, though it's likely out of service. Perhaps twenty years ago my wife and I were 'fanning Fostoria and were admittedly trespassing close by the tower. Out of nowhere, a group of "suits" appeared and we thought we were cooked. One of the men walked up, introduced himself and nicely asked me if I knew what the value of his Hamilton 992 pocket watch might be. My heart rate slowed down considerably and we had a nice chat with no warnings. It was nice to find a kind and human side of railroading that I thought had vanished. Nonetheless, after a train passed, we made an expeditious exit.
Yes, tower is still there. Control of the area has been transferred to the "IP" dispatcher, currently still in Indy. Change was made about 2 years ago.