I'd call that inner a "partial", unless that 'inner' also has the inside wall where the vent hole is, and you need that inner area, I'd skip it, you can always get it later if you need more than the 'outer' - what exactly are you needing to repair? the main problems in that area are usually the very bottom where it drains the vent space and the weld-nut mound on top where the fender mounts .... there's also a 'deflecting' piece inside which keeps water from dribbling in the vent that gets rotten - that may [or not] be on the other side of one of those pieces
Bill
