This hose right on top next to oil cap

Hose marked with blue around it

 

See if this matches what you have:
https://www.partsgeek.com/7kc8pvl-je...m-harness.html

 

I see a plastic coolant football and large stell injectors, so that's a Renix and that is the correct part.
NAPA and Dorman part numbers at https://cruiser54.com/?p=121
That side of the harness was $20 on Amazon when I bought one last month.

Nice use of copper plumbing fittings in your elimination of the heater control valve.

 

Dorman 46003

If I recall correctly, comes with a line for the fuel pressure regulator, two that sit directly in front of the throttle body, the one you’re missing, and one to the front of the EGR transducer.

Check to see the condition of the other side of that harness - it comes in two pieces. If one half is old, the other half could probably use replacing as well. They’re both inexpensive.

 

FWIW, I 'adhered' mine to the valve cover using RTV. I was in a pinch at the time, needed the vehicle for the next ay, and figured I would RTV it in place then order the replacement. Well then, at the time I couldn't find a replacement. Eventually I just let it be. That was about 8-9 years ago and it's still holding. The key is to get the hose and valve cover surfaces as clean as you can with solvent. Make sure to let the RTV set up firm (overnight) before re-attaching the hose. But it wouldn't hurt to buy a replacement while they're still available.

Also, make sure the small hole in the rear valve cover rubber grommet (where the small tube attaches) is 'open'. If it gets plugged (common) it will allow more pressure to build up in the engine and can pop the larger hose out. Or at least that's what was happening to mine.