Thanks for the feedback amongst the many things we discovered during this project was that maybe not so much with the backrest in place but the factory mounts are somewhat variable hence the slotted holes, also really hard to find black screws that a supplier would guarantee would not corrode on us very quickly, Honda uses some exotic process that nobody was able supply anything suitable in the time we allowed so for now its stainless hardware.

we had hoped to find some bolts with larger heads but if anyone feels they need some washers I am happy to mail some out to you.

I may look into some rubber caps to drop into the holes to hide the mounts.

Overall I am pretty happy.