You honestly should have no issues with a 4BT finishing the trail if you fill up in Placerville. With a 23-24 gallon tank it shouldn't be too hard even for teh 2F guys. Its always a good idea to bring 5 gallons, but this trail is only 12miles long from Loon Lake all the way out.
I have run it with a built 302 in a 72' Ford Bronco with only 18 gallon tank. I had at least 1/3 of a tank left after running from DoRobbs all the way out.
I have had my fair share of major carnage on the trail itself. Pulled a steering box off the frame just after Little Sluice. Broke the ears off of it, so using new bolts wasn't an option. We had to drill the frame and run a u-bolt through the frame to hold the box on it. I did the last 99% of the trail in 2wd. We aired up the front tires, and I would only lock the front hubs for certain spots that I couldn't drive in 2wd. Made it out, and drove it around Tahoe back to DoRobs that way.
I've done the Con at least 8-10 times now. Its a great vacation, but be prepared. Big Sluice isn't too much of a big deal since the whole thing is pretty much down hill. Cadillac Hill is tough mostly at the bottom unless its real wet and sloppy. Anyone who values their body and parts at all will steer clear of Little Sluice. Its really just a buggy type of section. Its only 50ft long, but its just plain nasty.
Go in the attitude to just survive the trail. Take the bypasses when necessary, and don't run stupid lines to show off. 12 miles is a long way when you have a large group of other rigs depending on you to make it through.
I love camping at Spider Lake, Buck Island, and Rubicon Springs. You can swim (its cold though), fish, and just kind of relax.
If you come in early and want a great place to camp or rent their cabins the night before you hit the trail, I highly recommend DoRobbs. Its closer to Loon Lake than Icehouse and is a great place. Its changed ownership quite a few times over the last few years, but they have a full restaurant with bar, and provide much safer tow rig parking for a fee. They make a great Bloody Mary too. The are right off Icehouse Road as well. And, they allow fires, even when you need a permit on the trail or even when fire restrictions are in order on public land.
I would love to make this run, but seriously doubt my 60 will be ready for the Con by then. I could always bring my 4runner, but if you guys only want wagons, I would be out.
On another note. Make sure to save some room on the camera for the drive out 89 around Lake Tahoe. Its an epic drive around Lake Tahoe, and you will chit yourself when you get to Crystal Cove and look down on it.
Here is a pic looking down on the slabs. Its a huge playground area.