I’m pleased to have found a possible chassis to house the power transfer controller (PTC).

The included heat sinks are a nice feature, as I expect that the main switch (transistor) of my design will get quite hot, as will the rectifier. I’ll probably need to enlarge some of the holes to accommodate water-tight fittings for the power cables, and may need to seal other places with liquid gasket, as any equipment going on a bicycle eventually gets rained on.

Actually, this chassis has way more space than is probably needed. Maybe I could keep the heat sinks as they are, but cut the other sides in half.  As-is, this chassis is wider than my bike’s rear rack.