I'm installing a 6AL for a friend on his Roadrunner.

We're using the Mopar electronic distributor to trigger it.

I couldn't get it to fire initially so I did the green to purple jumper with the key on. It worked fine right off the box. I then tried to jump the leads on the pigtail right next to the distributor. Very intermittent. It simply would not spark but about 1/3 of the time. I replaced that segment the of wiring and it seemed to trigger better. Pulled the distributor out and it seems to trigger if you spin the shaft at higher RPM but not slowly. I did check a couple of pickups to make sure that wasn't the problem and checked the gap.

Is the box the issue?!

Positive side feeding the box is directly off the battery and the negative side is too.

turn on lead for the msd gets 12v during crank and run from the ignition?

I'm using the blue wire that originally fed + side of the coil. With the key on run I get good solid spark down near the box. It seems the further away I get the worse and more intermittent it becomes.

i had a problem in my coronet when i put a 6al in, it would barely fire off when i let off the key from start. it was ign1 or 2, i forget.

turns out the wire that i was using didn't get voltage in start, only run. i had to tie the ign1 and ign2 wires together to feed the msd turn on power. give that a try.
i was working at the bulkhead, since much of my stuff was butchered...

The blue wire goes dead during cranking unless you have the stock ballast resistor in place and a factory, functional ballast resistor bypass wire connected to the stock starter relay.

Ballast was in place but I bypassed temporarily with jumper wire.

You'd still need the wire from the starter relay to the coil side of the ballast resistor. It's easy to put a test light or voltmeter on the wire and see if there's voltage while cranking.

Again, I haven't gotten to cranking yet. How would the switched power lead to spark being okay at the box but intermittent at the pickup?

I have it wired exactly the same as my '63 and it works perfectly and fires instantly!

The blue wire the connects to the coil positive has power when the switch is on both start and run... IMO you have it wired correctly

Exactly! That's the way it is on my car and even in the MSD diagram. It DOES have spark to the distributor. You spin it by hand at higher RPM and it's fine. At cranking speeds, though, it doesn't spark.

I'm beginning to think it's a bad box...

so you have voltage during crank and run.

the car won't run?
or the problem is your are not getting spark when spinning the dist slowly?

I installed 3 6AL boxes with a Mopar electronic distributor, blew all three, spoke to MSD, they said they were compatible. They would work for about 10 seconds, than die.

Installed the old MSD unit, worked fine.

Installed a new MSD distributer with a new 6AL box, no other changes, still working. I took one of the boxes apart, it had a burnt out quad driver in it.

about two years ago i put an msd streetfire on my powerwagon, factory electronic dist, haven't had any problems at all.

An update on this. My friend ordered an old style analog MSD 6AL off of Ebay and I installed it today. It fired up on the first twist of the key!

Nothing like wasting an entire day working on something only to find out the brand new box was trash!

So analog isn't always bad.

I've been hearing bad things about MSD here lately but didn't want to believe them...

The MSD tech was worthless and pretty much decided not to help with anything after he found out I was hooking the box up to something other than an MSD distributor. It's a magnetic pickup distributor for chrissakes!

Time to start hoarding the old stuff...

....and hence the reason I'm still using the old school box. Sure like some of the features of the new digi stuff though.

Exactly!

They almost had me convinced to upgrade mine a few months ago.

Not now!

I run a MSD digital 6 box and it has worked perfect for the last 5 years.

I'm already well into the hoarding process.