Replaced the rear shocks with some used Progressive 412 units that came from a non-Sportster. They are measuring 14.25" long and had worn out eyelet bushings. I ordered the new bushings from Progressives for about $20 and pressed them in after pressing out the old ones.
The bike seems to handle a lot better with more suspension travel and slightly higher leaning clearance. It definitely feels firmer over bumps, but overall very good.
The old piggy-back 1200S shocks I had on there served me well for about 15 years. Now they seemed tired out and I wanted a change in handling. I am not one to lower my bike for the looks vs. performance, so I went the way I went. I also lucked into the used Progressive 412 shocks for $64 delivered on FB Marketplace. They were in very good shape except for the bushings.