he's reporting a no crank issue as well, so probably not fuel relatedI'm thinking fuel pump too. Get a modern code reader like this:
Get the Torque Pro App if you have an Android phone and set it up to read codes and fuel pressure.
most likely going to be a ground or "maybe" even ignition related
my first thought was "security" but that will either do one or the other, not both as far as I know on the gmt900's
op: when you get back to it, start at the battery first, take the cables off and look for any hidden corrosion, even if they look clean wire brush them and re-connect.
that's a starting point.