Thanks for posting this! I'm about to give this a go. When you say disconnect all electrical connectors are you talking about the ones on top of the tank through the access hole under the second row seats?I just found and fixed my leaking gas tank, and installed the GM charcoal vent canister.
The gas tank leak was exactly the same location as others show in their photos. Small crack, maybe 1/4” or 5/16”, and it was tight, hard to find. The metal in the area around the crack was slightly distorted. I don’t see the crack increasing in size as long as the charcoal canister does it’s job and keeps the tank from pressure cycling. The tank pressure cycling between pressurized and depressurized causes fatigue failure at the crack initiation site. That’s why the crack is in the same spot on everybody’s tank; the area that gets the most movement from pressure cycling, and a geometry prone to cracking (stamped rib in the tank top). Think of it the same way a piece of metal breaks when you bend it back and forth many times.
It was super simple to partially lower the almost empty (on reserve) tank on a jack, and access the top of the tank from the front. Make sure you disconnect alll hoses, electrical connectors and fill nozzle hose and vent hose. You will need to lower the tank maybe 8” to get enough room to work in there. My truck is lifted 2-1/2” so I was able to sit at an inverted position and get my shoulders and head, and 1 arm up in there to clean the paint off by hand with coarse sandpaper. Or, you can use a grinder and blow-up
I cleaned all the paint off the tank 1-1/2” around the crack I used JB Tank Weld, which is a 2-part putty, I made a putty patch that was 1-1/4” in diameter, and 1/8” thick. I tapered the margins to the tank, and painted any remaining bare metal.
I know there are those out there who likely believe this repair epoxy repair to be sub-standard, but after I looked at the situation, I believe the structural integrity on the tank will remain, post collision, at least up to the point where the original (new) tank would have. It’s a tiny crack and in an area not prone to ripping or failing catastrophically.
Address your leaking tank - I’m glad I did.