Engine bay oddities around fuel filter questions

[dpom75]

So i was finishing up my heater core replacement, and after putting everything back together, I snapped a few pictures of some things that seemed out of place and I don't know where they go, what they do, and if I need new ones.

One is a picture of the top left of the fuel filter housing, open inlet with nothing on it. What should go on it?

Second is picture of a hose coming out of bottom of fuel filter housing, possibly it connects to the top of the housing on the vacant inlet?

Third are pics of a sensor hanging out new the fuel filter housing, no idea what it is, where it goes, and if I need a new one.

Any help? I am new to the 6.2l engine. This is on a 1990 Chevy Blazer 1500 Silverado with A/C.

 

[campfire]

Not sure what the wire is, but both of the two lines you have pictured are drains. The top one should have a hose running down toward the fender area. On my Suburban, one dumps on top of the frame, and one dumps on top of my tire

 

[Big Ray]

The upper nipple is an air bleed, and I'm pretty sure the lower is a water drain.
IDK about the wires, maybe a water in fuel sensor...

 

[campfire]

The upper nipple is an air bleed, and I'm pretty sure the lower is a water drain.
IDK about the wires, maybe a water in fuel sensor...

That's correct about the nipples.

But WIF is inside the filter housing. You can see both of the filter housing electrical connections in the pictures, so this is something else. The weird thing is I don't recognize that connector. Where do the wires go?

 

[Big Ray]

o.k., I did some snooping around & found this

and this

I have no idea where your plug goes.