If when attempting to install an H&S Mini Maxx you come across Unrecognized Part Number "SPRAxxxx.MM" this indicated that a Spartan Tuner has been previously installed on the PCM. Spartan Tuners essentially hijack the the PCM and leave a footprint that prevents other devices from being downloaded. The truck needs to be re-flashed back to stock or "as built". Typically a diesel repair shop or dealer can take care of this using an Integrated Diagnostic System (IDS). After the PCM has been flashed back to stock as it came from the factory you can install the H&S Mini Maxx.