Battery in Trunk

Simple.

Wire in the ford solenoid using the OEM starter trigger wire connection. The one that runs from starter relay to starter. Good sized ground (same size as starter cable) to chassis at rear if frame connected and another ground cable off engine/trans to frame rail.

Run a heavy gauge cable forward from Batt+ to alternator. A 10 gauge to the rear of the car is not heavy gauge. It needs to be a 6ga minimum

Should be 90% done with those items.