I always do it by loosening the line at the caliper, then unscrewing the caliper. Leaving the junction of the hard and flex lines alone seems to have the best result.
ABS; in the engine compartment, follow lines to where they go; if they exit the master and leave the area through panels to the brakes, no ABS; if they go to a box that's partly metallic silver and black plastic, about 6x6x4 with a lot of brake lines to and from it, and mounted just in front of either side shock tower, it's ABS.