A Photo & Discussion Forum for Wharram Design Enthusiasts
That looks very much like the foremast case on a tiki 38. If so, the pad at the after end of the case is designed for a regular winch for the anchor rode. There should be a roller on one side of the cleat to hold the line clear of the case. I guess you could mount a windlass on that plate. FWIW the plans were revised on the T38 to add another layer of ply under the pad for reinforcement.
looks like a nicely built boat!