Ref Trumps 757 Mr Trump has been using LGA as his base for his 727 and now 757 for over 20 years. As far as the former FAA Tower the base or stump as you saw is part of the D Concourse used by American Airlines, and due to the architecture of the concourse it would be impossible to remove. The reason the main upper part was removed it blocked controllers in the new FAA Towers view of the intersection of LGA's two runways, so kind of a pretty good reason to remove it despite its historical value.
Cheers
LGA777

