Engine bay switched 12v power

[jaykay]

Yes, at present I am separated from a FSM (full service manual) access, but I do recall difficulty in using it to determine which leads are switched 12v. To an electrical neanderthal like myself this is pretty much a needle in a haystack but I will give it a go.

#1 power a number of loads in the cockpit via a terminal block. IIRC the block can handle 35 amps coming in:
-shift light;
-l and r fan switch latching relays;
-engine compartment fan latching relay;
-ipad charge;
-foot well lighting;
-machine guns;
-camera;
-phone charge;
-secret stuff;
-engine gauges.

I would think the 7.5 amp phone connector powering the terminal block would not work. The fuse would certainly pop as the draw from two of the above loads would kill it. Hence, the original question: how to best safely tap a 30 amp circuit from the footwell fuse box.....phew. And ground it....properly.

#2 Power an engine gauge sensor module to be located on the trunk firewall with ignition switched 12V power. The load is fused at 5 amps. Sensor wires will be routed through the trunk firewall somewhere. I think the engine bay itself will be too harsh for it.....