Sudden Death 93 Sport Fuel Delivery?

Here you go- http://www.then-now-auto.com/fuel-pumps/

My 93 Sport was running great (forgive me if this sounds like 50 other posts... I'm on vacation and don't have the time to read every post and find my answers the hard way).

We were just running around the lake earlier and it was finally calm enough now that the weekend crowd is gone to run WOT and it did just fine. Read just over 4500 RPMs which I would guess might be the tach being a little off since I'm pretty sure I'm all stock here - except the ProTec ignition has long since been replaced by what is apparently a coil and Sierra Marine dizzy- I think Keno asked for a picture of it on another thread...

At first I thought it might be the coil or something - it's been hot out and I had just run it hard earlier but further investigation made me question that theory.

When I tried to start it, it turned over just fine and at first it even sputtered like it might run - started missing badly, died, then nothing. Keeps turning over but absolutely nothing.

Why I moved on from thinking it was the coil/distributor to thinking it might be the fuel pump or some other fuel issue:

It has a clear fuel line from the pump to the carb. I can see that there's no fuel in the line before I crank. As I crank I can watch the fuel jump up the line but it seems to be pulsing and never quite makes it all the way to the carb... My thought started to become that when it sputtered before, it tried to start on what was left in the bowls and then died of starvation.

I can watch after attempting to crank as the fuel slowly goes back down the line, into the pump, and presumably to an equilibrium where the level is even with the tank... or something.

So my first question is, would it be in any way normal for the fuel to go back down the line when the pump wasn't running?

And if the pump worked, how fast would it fill the 18" of line to the carb and feed the bowls?

I guess there could be a fuel pickup or filter that's restricting flow but that wouldn't explain why I could run around for 30 minutes at 3500-4000 RPMs with no issues and then all of the sudden nothing. I mean it would be some kind of freak occurence... I run marine gas, I put fuel stabilizer in it anyway, and it has more than a half tank in it.

So before I haul off and buy a new pump (I can't wait for a rebuild right now) is there some other reasonable explanation? It's really bothering me that the fuel creeps back down the line when the pump isn't running - but that could be my ignorance of what normal operation is for these.

I have some pics that probably aren't helpful but I can't post them right now because my phone refuses to let me have them until it's got more charge.

Anyway, any help would be appreciated and I apologize if I say anything ignorant - you guys already got me once for saying I put my impeller in backwards when I meant RWP... I can take the abuse if it gets the problem solved...