Yes, the Curt Hitch part # C11364 will allow you to retain the spare tire mounted underneath your vehicle and will fit your 2015 Fiat 500L. I attached an install picture that shows the hitch installed with the spare tire intact as well. view full answer...
What the diagram is trying to show is that the bolt and spacer block get routed through one access hole and the bolt will stick out of the adjacent hole with the block keeping it in place. So the block and bolt head are inside the bumper with the threaded part of the bolt sticking out.
The bolt and block will need to be fishwired into place by running the bolt leader through the hole the bolt will eventually stick out of and then out through an access hole. You will then put the block... view full answer...