I dont know if the shift cable you currently have will still work with the slap shifter. The NSS location is I am thinking up to you since Colorado stated that he moved his somewhere else and it obviously works. Shiftworks looks to have all this available to keep the NSS down on the shifter, but I would call them PH: 702-895-6812, and tell them exactly what your changing from and going to and that you have a 69 shifter and ask them because I dont know what the difference is between the ST300 and TH350 besides gears. The guy there is very helpful and will be able to tell you what you need or dont need to make everything mesh together correctly.