1st US Army / XII Corps

[HorseSoldier]

In the post-nuclear chaos and displacement, I'd think that just about anybody who could grab control of port facilities or interdict rail lines might end up in possession of some armor. This could include MilGov or CivGov units who diverted stuff headed for the front because they felt they needed them more, New America enclaves, local warlords or communities, or even Mexican/Division Cuba forces who overran ports in southern California and Texas. I doubt there was all that much stuff laying around to begin with after almost a year of high intensity conflict in multiple theaters, but it could turn up most anywhere in most anyone's hands by 2000. (Access to a good deal of military kit might help explain why the Warlord of Memphis seems to have been such a pain in the ass for MilGov, for instance.)

As far as armor repair/refurbishing, Anniston Army Depot in Alabama does rebuilds on M1s and assorted other AFVs in real life. I don't know if they were the only facility set up to do that work in the Cold War era. I'd think doing even extensive repair work in theater would make better logistical sense than shipping damaged tanks back CONUS and then back over to Europe or where ever in a WW3 scenario where sealift and airlift have to have been badly stressed.