With it being well over 60 degrees today, it was a perfect day to work in the driveway and peel the intake and valve covers off Rob's 8.1 so we can fully assemble the new engine before pulling his Blazer in the garage to swap it out.
Once the intake was peeled off there was no question about it, that it definitely died of fuel hydrolock from #3 injector. Gas was even well up into the intake and went everywhere when I popped the intake loose. I also noticed fuel poured out of the fuel regulator when I unplugged the vacuum hose as well. The vacuum hose!!!

I've never seen that before!! Makes one wonder if the regulator was a chicken or an egg.....did it fail and shoot the fuel pressure to the moon and damage the injector or ??? The injector looks fine externally.