Sometimes people discover that the rear caliper bleed screw hole is not actually the highest point when installed after these conversions, because they're not designed for Z cars. It's close but still has a spot for an air bubble. They have to unbolt the caliper and rotate it so that the channel to the bleed port really is the highest point. They bleed the brakes with the caliper loose, then rotate it back and bolt it down when they're done. Be the bubble.