Raymarine doesn’t label their Network Ethernet cables as such but that’s exactly what they are. Ethernet cables come in 3 forms, of which two are relevant to marine networks: cross-over, which allows device-to-device communication, and straight-through, which is meant for device-to-switch communication. Back to Raymarine, cables that are waterproof at both ends are meant to connect two devices (for instance a c90w and c140w) and are therefore cross-over cables. Straight-through are cables with one waterproof end and the other end the standard RJ-45 connector, meant to interconnect device to switch. All Raymarine devices with the exception of the Raymarine Switch (part# E55058) are meant to interconnect with Waterproof connectors. The Raymarine switch is meant to use the standard RJ-45 connectors.
The problem you encounter routing cables through a boat with limited space is quite common. The approach we use here at PYS is to route the small RJ-45 connector through the smaller openings. The set up depends on many devices you have to interconnect. If you have between three to eight devices, we recommend you use the Raymarine Switch. When you only have two devices, the cost-effective solution is to use the Raymarine cross-over coupler (part# E55060). In summary, Tim, use two Raymarine straight-through cables connected to a cross-over coupler so both devices can be networked.