Re: 1969 Chevelle Manual Drum Brakes
Having driven my 66 for 2 years with the original four wheel manual drums, I can say that, if in decent shape, or at least intact, they will stop ok.
However, I just finished the install of the Ground Up front disc conversion kit, also manual, I love it. I also got a complete set of new brakelines and new flex hoses. Highly recommended. I have way less than a grand in it.
I checked into the options, but figured that I would spend a couple hundred bucks for any partial upgrade, so I kept the drums working. I did a couple of salvage yard sweeps and found nothing. The chances of finding usable salvage stuff is pretty slim. You can try simply installing new or reman stuff from the parts store, but you will spend a lot of time and money getting all the stuff. The kits are the way to go.
Power drums were an option, so that may be the easiest way to go, with a new booster and master.
My priority was getting a dual master and disc brakes, so that's what I did.
66 Malibu Coupe, home rebuilt 350. Took me 39 years to get her!