Mary, you can buy a new seat retainer insert socket, for the empty hole in the fender for about $5 (which is the socket and C clip) if you opt for a solo seat. Use a medium size Zip tie to hold socket and reach up between tire and fender and "eventually you will poke the pointed end of the zip tie out and thru, guide it up, snap the C clip and your done...the solo seat will have a hold down point.
BTW, you might pick up the new 2010 HD Parts and Accessories Catalog...they have a whole bunch of new stuff for Sporties including seats, fuel guage that replaces the cap on your master cylinder front brake cover...way cool...expensive but cool!
I have a fatbob and it's great. Gives the bike a better look, but a big tank on a stock bike needs some extra stuff, I also have a Mustang seat and leather bags. Gets me about 150 miles before I need fuel.
Ive got the 4.2 tank on my Sporty, and I get about 180-200 depending on if Im hard on it or not, lol....But if you do change ur seat mary, and need a factory seat of a XL custom, Ive got mine just sitting in the garage since I went with the Sundowner seat.
p.s. I wasnt sure if thats what he meant by a custom sporty seat, which is why I offered, if Im wrong, my appologies, lol.
Don't feel bad about your tank size,went for a ride with a buddy who has a Ducatti Big dog.We left home with full tanks on a 180 mile ride we had to stop twice for him to fill up:small3d031: