Lessons learned when prepping concrete for staining...part 1

1. Be prepared to invest a lot of time and hard work, especially when you run into a thing called "cutback" aka black mastic used in the olden days to lay vinyl or asbestos flooring.
2. Instead of using old towels to sop up oily mess from tar residue, or from cleaning, use Oil Dri, or the equivalent to the stuff at Home Cheapo. Don't waste your time, money or heartache on anything other method.
3. A wide, flat putty knife is a hell of a chisel when removing mastic-soaked thin set concrete.
4. Look into something called Bean-E-Doo by Franmar. It's a soy-based mastic remover that helped a ton.
5. If you don't feel like BSing with enviro-friendly products, look into Strip Klean Mastic Remover for the first part of the job and for touch ups
6. Never underestimate the power of help from others!
7. Don't lite a match

I hope this helps someone else with this godawful, but rewarding process. So if anyone tells you it can't be done, well it can... at a laborious cost.