Step 1. Save the Jonathan's Performance custom tune from your email to your computer.
Step 2. Connect the HP Tuners RTD+ to the vehicle and to your Windows10 based laptop or tablet, and open the RTD+ Flasher software.
Step 3. If you have already purchased credits for your vehicle, go to "Help", and click "Resync Interface".
Step 4. Go to "File", "Open", than select the custom file.
Step 5. Click "Write Vehicle", and follow the licensing instructions.
Step 6. Once the custom tune has been written, you're ready to datalog! Follow those instructions HERE!