starting problems

It takes very little voltage to close a relay. That's why 99% of the time we will hear a relay "click" whenever a starter, battery, or its connections fail.
Thus the smaller wires that feed everything except the starter itself ( as in madelectrical bs ) cannot be the problem in this case. Doesn't matter now though. Get yourself a volts gauge and carry on.
For a more positive comment, you did get rid of that POS add on battery terminal before winter sets in.