Today I offered a friend a section of glassfibre painter pole, with a vertical split to allow it to be squeezed into the scupper as a bearing for an emergency rudder. On my 2012, it is a perfect squeeze fit, but on the rear scupper of a 2013, it "didn't touch the sides".
Obviously Hobie has changed the molds to allow lining the forward scupper for strength when on a trolley, but the rears, while also enlarged, do not have the lining. Anyone building an emergency rudder using the scupper should be aware of the different diameters.
2012 Tandem Island "SIC EM" with Hobie spinnaker!