69 Dart - relocate rear leafs ?

i am slowly working on my 69 Dart 440 project. One thing I am seriously considering is moving the rear leafs springs in. I am looking at the USCT kit for about 220 plus ship. It bolts in for location , then weld it up. I was under the car, giving it a look over , and it looks like if you move the pass side spring to the frame rail it will be VERY close to the fuel tank . Has anyone had this issue ? Any tips on what to do and what not to do ?
Thank you