Just a thought, in Seattle the former Renraku Arcology was turned into public housing (and not far off from being a prison for the poor, it is not so easy to go in and out). Of course it is best known for when the software running it achieved sentience and took over the place and killed most of those inside, but that was decades ago, once the city took it over (first calling the ACHE and then SPIRE) it has 'merely' been a cesspool of poverty, desperation, and inadequate maintenance. But hey, at least you are out of the acid rain.
Over 300 stories tall and vaguely pyramidal in shape (slight slope on the bottom half, more pronounced slop on the upper half), bottom five floors are a mall, but it is hard to travel between there and the housing component.
Of course you can make your own megablock wherever you want, I'm just mentioning this as it is a nice tie-in to existing ShadowRun lore.