Yeah, crap rims, but the hubs are good enough to get delaced and cleaned up. Sooooo glad I asked, because I would never have considered how hard it has to be to get a cassette off with the rim gone.
Thanks much for all the tips, and I'll check what I have against the database and let you know it its not there.
A cassette is pretty easy to get off without the rim. All you need is a chainwhip and a cassette lockring tool. Freewheels are next to impossible.
Detension before you cut.