I purchased a set of Progressive rear shocks and springs from Michael Morse last year and got around to installing them over the winter. Michael recommended going to a 13-1/2" shock which he indicated would make the bike handle better so that's what I ordered. When I tried to install them I found that the lower mounts on the swing arm would hit the exhaust pipe due to the additional length. I didn't want to modify the exhaust so I reordered shocks in the standard length. The Progressive shocks and springs were close to $300 and are still new in the box if anyone is interested. I would sell for $150 plus shipping.
Mike
Mike