It lives! I left the block heater plugged in all night, woke up this morning, gave the intake a shot of wd40, followed by a hairdryer. After cranking for about 30 seconds it started right up. There is no longer any evidence of bubbles in the fuel lines.

I think my problem was when i replaced the return fuel line from the fuel filter to the hard connection on the firewall. It was obviously full of air which was being sucked back every time I stopped cranking. I attached a brake bleeder vacuum pump to suck fuel back to the firewall connection which solved the problem.

I hope my experience helps others who run into a similar problem. Thanks for all the help!