Seen a few members here who have used one of the skull license plate screws to fill in the rear hole in the fender when using a solo seat. Harley's price is $26 for the 4. Probably not going to lose 3 so don't see the need to spend that. I figure there have to be some folks here with 3 sitting around. So if anyone would like to part with one I'd be happy to take it off your hands for a fee

 

If you cant find a single one they might be chepaer at J&P cycles

 

I am under the impression that this particular design is only sold by Harley. I have never seen them anyplace else for sale.
J&P, Dennis Jerk, and others sell 'skull krommets' license plate bolt and nut sets.
But IMFUO, they would stick up way too far for your purposes.
Good luck, Chrome.

BTW, don't ya jus' love it when you git the scoot to the point where this is a concern. Details, it's all in the details.