Honestly I bought a Mustang Tripper seat and love it when I have my LePera solo seat off the bike. It has a nice deep bucket which results in good lower lumbar support and it has the cutout for the stock HD rider backrest. It allows me to flat foot the bike and I have about a 29.5/30" inseam. I found mine on ebay new for $349. I picked up the one with the 11" passenger seat portion for my SG which would look spot on on your dad's EG. It may be a little tough to see in these pics but at least its an idea.