from an 02 Launch, never installed. included are 3 transom plates, 3 platform brackets, and 2 of the 3 spring loaded retaining pins.
i paid $400 and change, asking $200
some measurements:
transom plate
2.5" wide, 5.5" tall, 1.25" thick
screw holes are 1.5" wide, about 4.5" above/below
platform bracket
16" supporting platform
2.5" wide