too much stuff
I have not worked on one of them systems for some time now, but adding another power steering pump and hydro crap would be very heavy and power consuming on a performance type car in my opinion. If power brakes are important and you have a large area for a canister, you can store vacuum in by using a check valve between the canister and the engine. I believe you can store several brake pedal applications in a large enough area, maybe a gallon or better size container may be required. If you are talking about the chevelle, then you may be able to find the real estate to place the canister somewhere under that hood. I think you are too congested on the front of your engine already, unless you are planning on deleting something else to make room for the hydro pump. what do you think pal?
Bruce