The top circle looks like an oil pressure switch? (Not the sender for the gauge)
Really too close of a pic
I'm going off of the oil filter on a 258 (in your pic) ------ (my filter is almost in my pic, my starter is at the bottom)
I swapped mine out for a mechanical gauge, so all I have is a "tube" entering the block
The inline fuse is a "Owner Add ON" and not something that is original----- Lights? Fan? No telling, unless the unit is still on, and you
can follow the wire to it
----JEEPFELLER