I keep a master project containing each grouping of connections terms, and seals options. All sunk into a harness that can be reported and copied into excel without a tool. It takes a bit but once set up they just need to be maintained and reported. Aside from that i have no other way of doing it. if you don't need the terminals or seals it is much easier because you don't have to provide an array of wire gauges to achieve your goal.
Regards