Do whatever it takes to get your carburetor spring and cable elevated to put them into a parallel strait line of pull. Your return spring should be at the top of the return spring bracket, and the bracket itself may need spaced up with a coupling nut or some washers and a longer bolt and stud. This is with an automatic kick down, but it should look similar to this. I think you also need Holley p/n #20-7 throttle lever extension bracket to put the cable attachment point into the correct travel arc. Oh, BTW, that’s a Great looking truck! What’s that color code and what’s it called?