I don't know if this will help but I have an 02 Low Rider and a lift from Harbor Freight that is similar the the one from Sam's. Harley sells a frame adapter for the Dynas. It is different than the ones for all of the other Harleys. Don't let them sell you the wrong one. It still doesn't mate up perfectly but it is a big help. The problem I have is that the Low Rider is too low to get the lift under it easily. I think the adapter is $20.00.
I have a lift from Costco, which is not the same as the sam's club but close. I have an FXDS-CONV and it mates up good with the lift. My son's Sporster however does not fit. We made our own platform out of two by fours, it works great and it cost next to nothing.
I've seen the new lift at sam's club and it looks much better than the old one they sold. By all means grab on to it; it will hard to beat their price.