Before you buy any bike rack it is IMPORTANT to make sure your Ford can handle the weight of the rack plus 4 bikes. Your owners manual may give you that information. I agree with others, carrying 4 bikes on an 1 1/4" class I or II bike rack is NOT a good idea. We have a 1 1/4" class II receiver and carry 2 mountain bikes on a Thule T2 917XTR platform bike rack and love it.
As others have suggested go to your local bike shop for ideas. Or check out www.etrailer.com/hitch-bike-racks. This was a great site when researching what we needed. Another thing you may consider is to take your Fusion to a shop that installs trailer hitches. They may also have some good ideas for you. Good luck