While my expertise extends more to 65-y8 braking systems, I believe in addition to a drum brake booster, you need the correct master cylinder for power drum brakes, and power brake pedal setup. All the parts were specific to their original application I.E. master cylinder bore, pedal leverage, booster strength etc.
If I were going to all that trouble, I'd get a disc brake setup going.
You will need, the booster, master, booster support plate, and brake pedal assembly.....
Nick
Despite what anyone may say, the arch of the brake pedal is completely different, I did this exact conversion and had to go and lay under the dash of a car in a swampy wrecking yard to get a pedal.
In the photo I was test fitting the assembly so the plate wasn't on yet.