You need to consider the use you want it for. If towing a big trailer, you should look at an FLD with the bigger motor options, but they will nearly all be a multispeed stick.
If you can be okay with a 190/230 hp engine, then an FL 60 or 70 is good, especially if you can find one with an automatic already in it. They will have the long wheelbase and a single rear axle.
Peter.