A 49 has "Huck" brakes; they're somewhat different than the 51 and on Bendix style. Each shoe is adjusted separately with Huck brakes, whereas Bendix take a single adjustment to do both. If you're not familiar with the Huck setup, a library may have older automotive manuals. You could also try "Chevy.oldcarmanualproject.com" for manuals regarding your car. After adjusted correctly, bleed the brakes starting with the farthest brake to the closest brake in that order. 2 people doing the bleeding, one in the car, one doing the actual bleeding, unless you happen to have a pressure bleeder. ChevyTalk.Org may also be of some help to you in the 49-54 forum. I am Butch/56sedandelivery.