Where's the skinny on the motor? What size is it? What static compression ratio? ~10.2:1 would be just right for that cam in a 350.
The cam will generate only 11" of vacuum. Strongly recommend an electric vacuum pump. You need minimum 18" to properly operate power brakes.
http://www.summitracing.com/parts/sum-760152/overview/
Do not risk your life on a vacuum can reservoir.

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