Ignition woes

[tsm1@domain.elided (Tom Mandera)]

Alright, I mentioned the '72 304 not starting on Wednesday.. I yanked the
high tension coil lead and pushed it back in, wiggling it carefully, and it
roared to life.  So last night, new plugs wires and coil wire.

Today, starts fine this morning, drive to work.  Starts fine, drive to school.

Leave school, no start.

Spins fine.  Pop hood, pull accelerator, gas squirts into the throat.  Got fuel.

Pull the #7 spark plug lead (longest one, and it's close the driver's door),
pull back the insulation, crank it, no spark.  Argh.

Play with coil lead... still no spark.

I then remembered a ground wire that was attached to the gray (now a darker
hue thanks to the soaking in p/s fluid) "electronic ignition" something or
other I spoke of before.  It's a points Holley dist on a '72 304, but this
square box with large heat sink fins on it is wired to the coil.  There was
a ground lead I hadn't re-attached.. hadn't caused any problems thus far...
but what the heck...

Swiss Army Knife in hand, I stripped the clipped lead, pulled a cowl screw
out, stuck the bare wire nder it, tightened down.

I then followed the wire back to a 4 (?) pin flat connector that attaches
this box (and other stuff I believe) into the coil.  The connector is at the
front of the motor, and wraps around in front of the dist.  I picked it up,
looked at it, put it back down.

Silly me, I did TWO things to try and make it run...

Touch the starter and it comes right to life.

So now I'm wondering... is that floating ground my problem?  I'll double
check the wires going to the coil, but I'm wondering if the floating ground
could be part of my prolonged high-rev problem.. 

I'll wire it up permanently tonight, and even add the body to motor ground
strap that's still dangling... ;-)

this random no-start is really bothering me.  But I *think* I'm getting closer.

I still don't understand what that stupid box is supposed to do... but it's
not earning any Brownie-points.

My only other thought is a failing coil?  Would it work sporadically?  I
have the coil off the '77 196... anything different between the '72 304
points and the '77 196 gold box coils?

Or am I going to just get fed up and dig out the Summit catalog for an
MSD... and trade for a new set of issues. :-)

-Tom Mandera, Helena MT
http://www.tmcom.com/~tsm1/scout