[dfwright]

You are correct. The "inner rocker" piece is included in the outer floor extension patch. The outer rocker will mate right up to the out cab floor extension piece when the repair is complete.

If you search the site for rocker panel replacement, or check out the project and builds section, there are lots of pictures of the replacement, including the outer cab floor extension you have. A lot of us have had to use that piece, as often the cab floor in the corners by kick panels, and in the back under the gas tank are rusted through in addition to the rockers.

You may also find once you tear it apart that there are a lot of other rusted out pieces that will need to be patched, like the lower parts of the A and B Pillars, and the lower parts of the kick panels, depending on how bad the rust is.