Hi, Somenewguy.
My handle is NewAtThis, and I certainly don't know as much as most of these guys, but I'm been fascinated with the 60-66 Chevy trucks for the past year or so, even though I don't own one (yet!).
I also plan to put a tank under the bed of my future truck.
There is an "easy" kit available at LMC Truck and probably other places.
http://www.lmctruck.com/icatalog/cbe/full.aspx?Page=37 It's $200 and doesn't look difficult. Essentially, it's a 21-gallon tank, which I believe is the same as what came on some old Chevy Blazers. You could get one at a junk yard, but you'd have to get the accessories to strap it to the frame.
Many people have done this modification, and they've put other tanks in there, too. But this one seems to be the most popular. The only problem I know with this particular tank is that it's so huge that it hangs down and is visible from behind the truck. I've looked for smaller tanks that should fit but won't hang down as much. These are not as tall, but I have no idea if they'd be appropriate for this application:
1941-48 Chevy
1949-52 Chevy
1953-54 Chevy
1971 Dodge Charger
1955-56 Chevy Bel-Air
Another issue is where to put the filler neck. They say you can't route a hose back up to the stock filler neck because it's such a long run and also it's part of the cab, which is not directly attached to the bed, so the cab and the bed flex independently from each other, which would be bad for your gas line. The easiest and maybe most popular thing to do is to stick the filler neck right in the bed and run it straight down to the tank. I'm sure there are kits for that as well. Personally, I can't stand the thought of drilling a hole in my bed wood and then taking the chance of dribbling gas on it when I fill up. There's a neat thing I've seen advertised that installs under one of the bed planks and then raises the plank up when you push a button, and that reveals the filler neck beneath the wood. Other people have experimented with placing the filler neck on the side of the truck coming out through the fender or maybe putting a gas door on the fender like modern vehicles have. I've seen posts where people who own 70's C10s have tried putting the filler neck behind a tail light that swings out. It looks neat, but I don't know how that would apply to a 60's truck.
Search these forums to find out lots about this. I know I've started a couple threads about it. I find it interesting. Also know that some folks might get mad if you mention it. They would say the cab is the safest place for the tank because it's totally enclosed, and the rear of the truck is the most dangerous because being tail-ended is a very common wreck. Seems like bolters are about 50/50 on this topic. And each group believes their arguments totally. I'm under the belief that a tank far from me and my family is the safest tank of all, meaning get it out of the cab! Also, they say a tank in the cab can get smell pretty gassy after filling up.
According to the government, the only safe place for a gas tank to be is between the axles within the frame. Whether it's in the cab or at the rear, neither of these fits that criteria.
So with that in mind, one idea I love is to place an S10 gas tank within the frame right beside the drive shaft. On the Chevy trucks with trailing arm suspensions, there's no room for that, but the 1963-66 GMC pickups had leaf springs in the back with no trailing arms. Seems to me that this might open up that area beside the drive shaft that the S10 tank. Exhaust pipes might get in the way, though. But I've never heard of anyone doing anything like that, so I can't recommend it. Just sounds like a safe option. By the way, the saddle tanks that were on the GMC trucks that were thought to be a hazard in a wreck were not in the position I just described. They were on the side, but not within the frame. They were outside the frame and only protected from a collision by the body of the vehicle.
For more info, here's a 6-page thread I started in Feb. 2010:
https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=641251&page=1Hope all this is useful!
Steve.
