i have done this on a few sets of hydro’s
you have 1 lever going running to the front brake then another hose attached at the caliper bleed nipple. (need to remove the nipple) to the rear brake. you bleed both brakes as a single system.
seem to work for the guy i did it for. also on the older gen hs33 i think you can run 2 hoses from the lever. i cant remember how you bled it though. i think you pushed it in from the caliper and had the hose bolt slightly lose so it weeped out.
please feel free to email me. (im away in belgium 1st thing tomorrow and scotland the week after)