The guy Paul linked to had the interesting idea to build a collection of short "Y" connectors to wire his CAN Bus. A "Y" was made up of two 4-pin Molex connectors with DB9 in the middle. The longer CAN Bus wires were basically extension cords with the opposite sex 4-pin Molex plugs to string everything together. Apparently his MGL Avionics manages to communicate everything with the two Hi & Lo signals along with +12V and ground. And they have cleverly made the DB9 pin assignments identical between devices. The idea was to have the flexibility of adding additional CAN Bus devices by simply plugging in new jumpers.
A couple of the Garmin devices have identical DB9 pin assignments (the GSA 24 Roll Servo and the GMU 11 Magnetometer oddly enough) but that commonality falls apart quickly. For instance, the GSA 24 Pitch Servo adds a jumper between pins 5 & 6 to specify it as the "pitch" servo. And other units have multiple unique pins.
My plan is to neatly bundle multiple cables to each device. As example, the GEA 24 Engine interface will have three cables: shielded pair for CAN Bus, shielded 3-strand for RS232 communications, 3-strand for Power 1, Power 2 (stabilized during engine starts) and Power Ground. Bundles will be tied with the traditional wire cord rather than zip ties.