Low vacuum reading

Was you hooked to full manifold vacuum? Your power valve should be half of inches of vacuum.

Hook to full manifold vacuum, set your vacuum reading as high as you can by turning the air/fuel screws back off 1". Adjust idle accordingly.

All of this should be done AFTER you have your timing set.

Timing first, carb second.

What initial? What mechanical? Set timing with vacuum advance unhooked and plugged.