Wow, lots of advice on how to detail your baby!

I think you are doing a spendid job.

Securing lines is a good idea for safety/longevity.

Parallel plug leads are OK if they are not touching.

PCV dissertation has a couple good points. My take:
- drawing air from the top of the engine rather than the middle (to the manifold) makes for less suspended oil but can restrict return oil to crankcase.
- No matter how you plumb it, the booster needs to "see" full vaccum signal and the crankcase needs to "see" a restricted flow.
- The crankcase flow should be restricted to prevent an excessive vacuum being set-up and drawing air past the seals (and killing them as well as drawing in dirt) and giving excessive "false air" to the intake.
- Momentary pulses of positive pressure will develop in the crankcase. Restricting the vaccum signal will lessen their effect on both the booster and the intake system.

Looking at your diagram, a restriction (orifice) should be between the oil separator/flame trap and the booster. This can either be a drilled plug in-line or a drilled plug in the branch of the "y" that goes to the trap.

Having separate lines for each vaccum signal is nice but that would require additional taps into the manifold somewhere.

Mike!
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Mike!