Sounds like the plugs are OK & likely the wires are also & I'm assuming 5/7 ain't crossed. I would ohm them & wiggle the ends as you watch the meter & power brake the eng at midnight with the hood open & see if there's a light show (grab a helper). You really need a vac pump (they're pretty reasonable) to check phasing/gap as the vac adv (only) alters phasing and gap so the pump lets you check em anywhere from no vac (what you have if on ported at idle) all the way to full vac. Holler how it turns out & what it ends up being