1/0 lugs with hydraulic crimper

Copper exposed to air oxidizes. This is why with old wire the stranding turns purple or blue 50' up the wire. With new wire solder and adhesive lined heatshrink the wire will still discolor but both loading and a 4 terminal kelvin bridge both verify solder is far superior. Too many examples around marine environment of crimping failures. A soldered connection cannot loosen or corrode. A cable can be squeezed until it farts but it still WILL corrode. Sneaky corrosion creeps UNDER shrink adhesive and attacks the wire and lug. If soldered wire brush off the salt air corrosion, scream at the boat crew then apply corrosion compound to seal. Without being soldered, you screwed, son.