You will want to buy front brake lines for a 67 Chevelle
If you use a booster, master, and the distribution valve from a 67, EVERYTHING will bolt right in.
I did this on my 66
72 Chevelle Booster/Master-----Must be a disc/drum master
67 Chevelle distribution block------this mounts on the frame.
72 rubber brake hose brackets-----your current drum brake hose brackets won't work.
67 Chevelle front brake lines----I chose the lines for a big block car----big block and small block use different passenger lines.
67 Chevelle power brake lines----booster to distribution.
You might want to add a proportioning valve after the master.
I did not have to----the brakes on my 66 Elky are working just fine---just a bit sensitive.
If you wist to avoid the distribution block on the frame (not easy to find and a bit pricey), you can get a prop valve and brackets to either mount in the stock 67 location (hard to get to and service) or brackets to mount it on the master/booster assy.
If you mount the prop valve near the master/booster, you will most likely have to get a set of brake lines for a disc brake kit----different than the stock routing.