engine compartment - what year identical to 98 v6 4x4?

This has been a nightmare. One takes out the engine; another installed the new engine.
I have gone to dealerships, used car lots to no avail.
I cannot locate where the knock sensors and where couple of tubes on my truck attach to. I have looked at 2000 prerunner version... and still no help.
Can you tell me what other year/model is identical to my truck so I widen my search and be able to see where these attach to? At the beginning of week after next, this truck will be my only transportation.
Thanks so so so much for your help.

 

Are you looking for the knock sensor location, or are you asking what wires are supposed to attach to the knock sensor?

... And what 'tubes' are you referring to?

 

I just purchased the knock sensor wires which attached to the "knocksensorwire.jpg". However, I cannot locate where th other ends of the knock sensor wires to go to. According to the book, they are attached to (2) knock sensors which locate between the firewall and the engine. However, I and (3) other mechanics (not Toyota) can't locate them.
This tube between the firewall and engine. As seen within the red circle - "metaltube1.jpg" and "metaltube2.jpg". I looked at the prerunner version and this tube does not even exist.
Another tube - "nonmetaltube.jpg", where does this go?

Thanks so so much

 

Not sure that this will be much help, because my 2001 with Cali emissions does not match yours, but that last "nonmetal tube" is coming out of an intake resonator, and it may be related to an emission system that your truck does not have. This could affect your air-fuel mixture because it may be allowing air to be indcuted after the MAF, which would screw up the AF mixture, I think (Just a theory, I'll have to let Ben and others who know WTF they are talking about chime in).

I would try this: turn on the truck, and while it idles, see if that hose has a vaccuum on it. If so, try pluggin it and see if the truck idles better or worse. If it idles better (you should be dead on 750 rpm when at operating temperature), plug that hose up permanently.