Well, theres 3 ways to sell them! ALL AT ONCE via the public auction method, or ONE BY ONE on a web site such as
eBay, or in SMALL GROUPS by advertising in national trade and collector magazines!
It all depends on how you need to market them and there are multitudes of marketing companies available to help you with it(at a fee of course). If you have the time and patience to do it, you can sell them individually through
eBay, on web sites such as this, through national advertising, or by taking individually priced items to national swap meets(transportation costs a lot).
The bottom line is that there are lots of different methods by which to market these signs and a vast lot of people that would be willing to help in your endeavor.
By the way, you picked a good web site to ask for advice because any information obtained on here will be fairly factual and honest and will help to guide you along. Also its free!!!
WELCOME TO OLD GAS!