You can definitely run this with a stock ecu. The only difference is you'll need to have your chip burned so that it doesn't reference the VSS. Lock up won't matter anymore. Speedo will need to be run from the aftermarket electronic to mechanical set up, or just use aftermarket GPS speedos. I'm running a Dakota Digital in my Monte Carlo that will reference the pulse from the T56 as the speedo. Very easy swap. ICEMAN cross members work great.