I hope you don't mind, but I am going to ask you this again. I understand that you bought some blanks - do any of the key blanks say, 'HD74' on them? Rad uses a standard blank that has several identifiers, but if you go to your local hardware store and ask for a Honda 'HD74' key blank it will most likely work with your battery and costs around $3. Again, I'm not concerned about 'F503' or that have bought some "universal" blanks online - I'm just asking about if the blanks you have say 'HD74' - if not, you can go to the store and get one. Worst case scenario is that you are out $3 dollars. I'd really like to save you some time and money. I should note, the Honda HD74 blanks do not work on bikes that are 2017 and before, new + bikes, RadMissions, and/or dolphin style batteries - but on your bike, they should. Best of luck.