I forgot about one method of transport that I used:

I strapped a front fender cladding to the outside of my suitcase once & checked it with the airline. There were a few raised eyebrows but they accepted it AND it arrived without damage. Hand delivered it to the new owner the next day. I've also hand delivered 2 sets of diff drop brackets in the same manner.

I know, not very apropo but it was an interesting experience.