mount the master cly. on the truck or and a bench vise ( I like to put it in a vise). then top it off with brale fluid and put your finger over the brake line hole and gently push the master cly. in and out. BUT everytime you your about to let off you cover the hole so no air can return back into the master. and do that till you have no more air in the master, then you can let you finger off the hole and the fluid should dribble out. slap it on and bleed the whole system.
