I have a 57 Chevy 3600 and I put a fuel tank out of a 78 Buick Riviera between the frame rails behind the rear axle. It fit with one alteration for the fill neck which required a half moon cut in the sheet metal under the tailgate. I hooked up the original fuel line and grounded it to the frame. I have been using it for 2 years now with no problem ... hope this helps in some way. Keb
