Using this intake horn and PCV reroute kit is straightforward. First, remove the old 2.4' OEM plastic intake horn from your 2017 - 2019 GMC/Chevrolet HD with the L5P 6.6L Duramax engine. Then, install the new 3.5' precision - machined intake horn using the provided new mounting hardware. If you choose the PCV reroute option, use the included hardware to reroute the stock PCV. Remember, it's recommended to do some tuning, which can be done with plug - and - play tuners or custom tuning. If you're doing a CCV reroute, you'll definitely need custom tuning. These parts are usually available in raw, illusion cherry, and gloss black, but powder coating takes about 2 weeks. For maintenance, check the o - ring gasket regularly to ensure a good seal. If the intake horn gets dirty, you can clean it gently with a soft cloth and mild cleaner.