This retrofit column is designed to fit your 1958 Impala and does NOT require modification to your original vehicle to install. Simply remove your old column, saving your original under dash mount and floor mount. Using an ididit installation kit, install your new steering column in place of the old. The 1958 columns will match the dash perfectly using the original bezel. These columns come complete with a neutral safety switch(shift indicator not included). The shift pattern on the column allows you to use either a 3 or 4-speed automatic transmission (except early Powerglides, as they have a reverse pattern transmission). A shift linkage(new or original)is required for installation and will attach to the lower shift arm provided on the column. Add an aftermarket wheel (using an adaptor)or original wheel but keep in mind that an aftermarket wheel may push the wheel closer to the driver and the original wheel will increase the overall length of the column towards the driver.