There have been 3 interior designs for Mirror dinghies over the years. They are, in order of appearance:
The Mark 1 interior has no stowage compartments, no drip rail, no inner gunwales (though these may have been added later), no stiffeners on top of the dagger board case, the thickened transom did not extend to deck level and there were knees from the side decks to side panels at the rowlocks and pads under the shroud blocks. This design was used on the first wooden boats, those with sail numbers 1 to 729+ (number of the last Mk 1 is unknown).
The Mark 2 interior design has stowage compartments, a drip rail, inner gunwales, the thickened transom extends to deck level. There are no knees to support the rowlocks and no pads under the shroud blocks. This design was used on wooden boats with sail numbers above 730+ (exact number of the first Mk 2 is unknown) and some GRP boats.
The Mark 3 interior was designed by Phil Morrison in 2006 for GRP construction. This design has no stowage compartments (but may have stowage options, such as bins, in the stowage bulkhead), no drip rail, wrap over gunwales, no stem post or shroud blocks, dished fore and aft decks, raised area on foredeck for mast step.
