Another approach...
The new positive battery cable I am looking at is 4 gauge with an 8" 12 gauge lead wire. Is it possible or advisable to take the 12 gauge lead and splice and solder a connection of the 3 fusible links (2-14 gauge and 1-16 gauge) to the 12 gauge lead. Heat shrink the connection and then individually connect the fusible links to their corresponding wires that lead to their terminal point?
mptc