I have a pretty standard Wide Glide. When I'm riding I always end up stretching out and sitting on the back of the seat . I was thinking that I could get a fat bob seat to put me a little further back but one of they guys at Harley Heaven told me this won't work and I would probably be better sitting lower on the bike. I am 172 cm or 5 ft 8 in, does anyone have any ideas?

Yeah, had a look but as I said the parts guy from Harley Heaven said to get a seat that sits lower and not farther back. Kinda thinking your way though.