Yes. Disc and Drum brakes mount differently, each uses a different spindle. Brake lines, hoses and master cylinders are also different.
The 1967 Ford Mustang had hydraulic brakes
My sources show there are different part numbers for spindles on the 1967-70 (drum brakes), 1971-72 (disc brakes) and 1973-87 (disc brakes).
Pontiac Firebird was created in 1967.
1967 Pontiac GTO cuz it has a bigger Motor in it.
1967 was the first year for the Pontiac Firebird.
1967
Front disc brakes were available on some models
yes
Total production for 1967 was 81,722 units.
389 and a 421 engine for a 1967 Pontiac catalina
1967
1967