The newer tanks will fit but you need to get the straps for the bigger tank or extend yours. Also it will hit the rear valance. You have to bow the bottom of the valance panel out to clear. Its not a big deal either way. Another alternative is to convert over to a Mustang tank. Click on the link and check it out. http://maverick.to/gtu_faq.php
The instruction sheet and pictures are very helpful, thanks! You mentioned an early mustang, could you give me a year and part number to use when I go to get the tank. Tony
The tanks are all the same from 65 to 68. This is the one I used. I believe it was ponydoc who has since told me he used a 69 tank, which is bigger, and he didnt have to shorten the straps.
