Dave, I haven't installed the DUI because I haven't had an engine in it since August. I'm dropping a 383 in it next week and will be installing the DUI then. Good luck with your problem.

I don't think there is a problem with the battery, but I didn't do enough checking last night and didn't give out enough info.  Battery is new (this spring) from Costco.  It has always cranked fast and always charged properly.  Last night I did not check voltage at the battery only at the distributor hot lead.   Tonight, battery is showing 12.76 at the terminals and now showing about 11.7 at the distributor with key at Run.  Still drops down to 9.5 (at dist) while cranking.  If batt was bad, I think cranking would have slowed down on Tuesday night quite a bit, considering the amount I did.  (Checking for fuel problems, messing around with distributor and then trying again multiple times, etc.)  It never slowed down.  Reason I was asking about a bad ground is it seems like losing a volt between the battery and the dist seems like a lot.  But I did check the engine ground tonight and it is all intact and the connections on both ends are tight.  Does it seem like I'm losing too much between batt and dist?  

Dan, thanks for sharing this link.  Seems like a pretty good unit and cool that it's made in North America.  Good price, too.  If the DUI unit that my friend had at one time doesn't work out I will definitely consider this one.  One question: Do you have to use the cap that it comes with or will a standard HEI cap fit?  

That looks like a standard base HEI, with an Accell coil/cover. The stock GM HEI cap & rotor should bolt right on, if needed. 

Yes, as Joel said it is a stock style cap that you can use a stock style coil and cover with.

Wow, am I embarrassed.    It's fuel, not spark.  I checked again using Ben's method (thanks, Ben) and could see regular sparking on #4 while my son cranked.  And then I put a little fuel down the throat and it started and run rough for a minute or two.   I'm gonna be mad if I got it towed and it was just out of fuel.  But I don't think so - only gone 155 miles on this tank, I've gone considerably more than that on a tank lately.  Hmm,  maybe trip meter died on me and I didn't notice.....  But probably more likely the fuel pump??  My 9 year old daughter was riding with me at the time and she swears that the bump we heard (sounded like we drove over a loose man hole cover) is the source of the problem - we did hear it right before it died.  Could it have been the fuel pump grenading on me?  Do they ever have catastrophic failures that make a noise?  I ruled out fuel at first for two reasons: 1) it died very suddenly and wouldn't run at all after that and 2) I could see and smell fuel squirting from the primaries when I was doing the parking lot diagnosis.  Maybe it just wasn't getting enough to run?  

I'm glad you found the reason for the problem Dave, Now to just find the culprit. :)

you can take the line off the carb add a piece of hose if necessary. run it into a container (coffee can) have someone crank the engine to see if fuel is being pump by the fuel pump.

|UPDATED|10/27/2013 7:50:09 AM (AZT)|/UPDATED|

Had that happen to me once...it was the filter plugged inside the carb inlet.

Yep, really embarrassed.  Poured five gallons in the tank and the  thing started right up.  Can't believe I didn't try that in the parking lot.  But I know I saw fuel going into the primaries, just must not have been enough.  $108 down the tubes.  Oh well, never will make that mistake again.