What is the correct year gas tank that will fit into my 68 coupe that will hold more fuel? I want more volume so I'm thinking a 69 will fit? Is their anything else special that I need to make this work?
A 22 gal from a 70 would be the biggest gain. The only difference is the height from the mounting flange to the top of the tank (basically, what you see in the trunk). You would have to cut your fill tube down a little and get a 70 sender, but other than that it bolts right in
It was my understanding that all the tanks were the same except for height from mounting flange to top. I put a 22 gal 70 tank in my 66 and everything lined up the same (hole centered). The fill tube was now too long and required a slight trim.
Like gp001 said all the tanks are the same bottom half with varying size top halves to increase capacity over the years. I use the '70 model (22 gallon) in my '66 project and all my friends are changing too as they need new tanks.