Plane mad Harry

Hi, I have just changed all 4 discs and pads on my Subaru impreza wrx 2002 bugeye and on the o/s rear caliper were I started I undid one of the bolts that hold the caliper together by mistake and some fluid leaked out, now when I press the brake pedal it is very spongey, do I just do a normal brake bleed starting with the furthest away or is it more complicated because of the ABS. Any help would be appreciated.