First if you need one rear brake line on one side you are not far from needing the other side. Also I would concider the ruber line over the axle, if it is original it should be replaced too. To bleed the brakes, start at the right rear
(its the farthest to the master) have someone push down on the brake pedal lightly untill the pedal goes to the floor or builds a lil preasure, while holding the pedal down losen the r.r. bleeder then tighten it back up. Tell your helper to pump the pedal slowly two or three times ( let the pedal come backall the way to the top each pump)(make sure your helper knows not to let up on the pedal even a little untill you close the bleeder it will suck air back in) then hold the pedal down and you open the bleeder again, repeat this three or four times check the master for brake fluid and do the same for the left rear. Never pump the pedal with the drums off. keep switching back (left to right) untill absolutly no air come out. You may have to do this whole thing several times (never letting the master fluid get lower than half full. If you pedal is low after your test drive note if its beter after you pump the pedal to a stop or if its always low. If always low its probably the rear shoe adjustment, if pedal gets harder it probably has some air still. ( good time to check emergency cables too) Hope that helps
(its the farthest to the master) have someone push down on the brake pedal lightly untill the pedal goes to the floor or builds a lil preasure, while holding the pedal down losen the r.r. bleeder then tighten it back up. Tell your helper to pump the pedal slowly two or three times ( let the pedal come backall the way to the top each pump)(make sure your helper knows not to let up on the pedal even a little untill you close the bleeder it will suck air back in) then hold the pedal down and you open the bleeder again, repeat this three or four times check the master for brake fluid and do the same for the left rear. Never pump the pedal with the drums off. keep switching back (left to right) untill absolutly no air come out. You may have to do this whole thing several times (never letting the master fluid get lower than half full. If you pedal is low after your test drive note if its beter after you pump the pedal to a stop or if its always low. If always low its probably the rear shoe adjustment, if pedal gets harder it probably has some air still. ( good time to check emergency cables too) Hope that helps