SilverSierra2005

Here's my problem I was wondering and would really appreciate it if anyone could help me out: 2005 GMC Sierra 1500 HD Crew Cab. Replaced broken 7 pin RV trailer connector. Everything did seem to be wired up correctly and I'm pretty sure it's all okay. Of specific note - tested with a voltmeter and had 12 V between 'the big red wire' and 'black wire' (ground) during the replacement process. When the connector was all bundled up and I was pushing it back into its mounting (stock) mounting bracket, there was a slight spark from one of the screws that one was supposed to tighten up to keep the contacts from rotating on the barrel of the trailer connector. The result: now I no longer have 12 V between the two wires. I checked 2 10 amp fuses in the instrument panel fuse box. One of them was blown and I replaced it. Checked a 15 amp fuse in the fuse under the hood and it was okay also. The only other thing I can 'see their' is something at/labeled 'Stud number two - 30 amp max'. I'm not sure what the heck that is even or how to test it or where I might be able to get a new one. Can anyone help me out - would be much appreciated. Supposed to go camping a week this coming Monday and need to get this working. I figure it's probably and hopefully something simple - just need to be able to get 12 bolts back there between those two wires. Might there be another fuse or something somewhere? Thanks!