You can find information in regard to the relationships between the two maps in the Appendices(
belegost and Nogrod), UT(
anchors(eg isle of himling which was the hill of himring in the first age), and The War of the Jewels(
scales).
Here is one of the better adaptations I've seen:
In regard to the mansions though they were damgaged according to the appendiced they did continue to exist and thought, it seems, largely abandoned during the beginning of the third age they were later reused. I will clarify a in a little bit.
[ July 18, 2002: Message edited by: Fingolfin of the Noldor ]